Special, clinical and ecological microbiology.doc

Module 2 Special, clinical and ecological microbiology

Text test questions

1.

Choose faithful composition of yolk salt agar

A.

*MPA, yolk, 9 % of sodium chloride

B.

MPA, ram’s , 9 % of sodium chloride

C.

MPA, rabbit’s red cells, 9 % of sodium chloride

D.

MPA, horse’s red cells , 9 % of sodium chloride

E.

MPA, glucose, 9 % chloride of sodium

2.

An outbreak of sepsis caused by Staphylococcus aureus has occurred in the newborn nursery. You are called upon to investigate. According to your knowledge of the normal flora, what is the MOST likely source of the organism?

A.

Colon

B.

*Nose

C.

Throat

D.

Vagina

E.

Smalll intestine

3.

Each of the statements about the classification of streptococci is correct EXCEPT:

A.

Pneumococci {Streptococcus pneumoniae) are alpha-hemolytic and can be serotyped on the basis of their polysaccharide capsules

B.

Enterococci are group D streptococci and can be classified by their ability to grow in 6.5% sodium chloride

C.

Although pneumococci and the viridans streptococci are alpha-hemolytic, they can be differentiated by the bile solubility test and their susceptibility to optochin

D.

*Viridans streptococci are identified by Lance-field grouping, which is based on the C carbohydrate in the cell wall

E.

No correct answer

4.

Each of the following agents is a recognized cause of diarrhea EXCEPT:

A.

Clostridium perfringens

B.

Enterococcus faecalis

C.

Escherichia coli

D.

Rotavirus

E.

*Vibrio cholerae

5.

Residents of an assisted-living facility are immunized against Streptococcus pneumoniae. What is the antigenic component of the vaccine?

A.

A protein toxoid.

B.

Killed whole bacteria.

C.

Live bacteria of attenuated virulence

D.

Purified toxin.

E.

*Purified capsular polysaccharides.

6.

An important virulence factor of coagulase-positive staphylococci is Protein A. How does Protein A aid in virulence?

A.

Binds the Fc region of IgG, decreases opsonization.

B.

Hydrolyzes secretory IgA.

C.

Binds Factor H, prevents activation of complement.

D.

*Extracts iron from plasma proteins

E.

Promotes tight binding of bacteria to extracellular matrix.

7.

A patient with septicemia goes into septic shock. Blood cultures later show the pathogen to be Neisseria meningitidis. Which component of the bacteria was most likely to be responsible for producing shock?

A.

*Lipopolysaccharide [LPS].

B.

Teichoic acid.

C.

A superantigen toxin.

D.

Capsular polysaccharide.

E.

Plasma membrane lipids.

8.

Which statement below most accurately describes the role of M protein in virulence of Group A

Streptococci [Streptococcus pyogenes]?

A.

Shows no antigenic variation, so is not a target for antibodies.

B.

Is a ‘superantigen toxin’ which stimulates TH cells.

C.

*Stimulates synthesis of antibodies that cross-reacts with heart tissue.

D.

Binds Fc regions of Immunoglobulin G molecules.

E.

Inhibit phagocytosis

9.

A child develops ‘strep throat’ (pharyngitis caused by Streptococcus pyogenes). The pediatrician explains to the child’s mother that the pharyngitis normally resolves spontaneously but nevertheless it is important the patient take a full course of Penicillin G. Why is this antibiotic treatment recommended in this situation?

A.

Shortens the course of the infection.

B.

Prevents spread of the infection to adjacent sites.

C.

*Prevents sequellae such as acute rheumatic fever.

D.

Stimulates development of protective immunity.

E.

Prevents spread of the infection to others.

10.

A patient has endocarditis produced by an aд-hemolytic Streptococcus. This usually reflects spread of normal flora to the bloodstream. From which site is this isolate most likely to have spread?

A.

Anterior nares.

B.

Facial skin.

C.

Lower respiratory tract.

D.

Distal urethra.

E.

*Oropharynx.

11.

From which site is a-hemolytic Streptococcus isolate most likely to have spread in blood?

A.

Anterior nares.

B.

*Oropharynx.

C.


D.

Distal urethra.

E.

Facial skin.

12.

A nine years-old child develops high fever and stiff neck. A spinal tap is performed. A Gram-stained smear of cerebrospinal fluid reveals many neutrophils and Gram-negative cocci that resemble paired kidney beans within leucocytes. Which organism below is most likely to have caused this infection?

A.

Escherichia coli

B.

Haemophilus influenzae

C.

Listeria monocytogenes

D.

*Neisseria meningitidis

E.

Streptococcus agalactiae

13.

A patient presented with upper back pain. MRI imaging demonstrated inflammation of the T8-T9 vertebral bodies consistent with osteomyelitis. A bone marrow biopsy, when cultured, produced colonies of Gram-positive cocci.Colonies on Sheep blood agar were 3-4 mm in diameter, off-white and beta-hemolytic. Colonies on Brain-heart infusion (BHI) agar were 2-3 mm in diameter and goldenyellow. Catalase and coagulase tests were positive. What was the most likely pathogen?

A.

*Staphylococcus aureus

B.

Staphylococcus epidermidis

C.

Streptococcus pyogenes

D.

Streptococcus pneumoniae

E.

Streptococcus mitis

14.

A 20-year-old women presents at a local clinic with fever and abdominal tenderness. She reports having had unprotected sexual intercourse a few weeks earlier. Gram-negative diplococci are seen in a Gram stain of vaginal secretions; many of the bacteria are inside polymorphonuclear leukocytes. Which virulence factor is most important in aiding this bacterium to initiate infection?

A.

Ability to invade cells.

B.

*Adhesive pili.

C.

Anti-phagocytic capsule.

D.

Endotoxin.

E.

Flagella

15.

Gram stain of CSF sediment from a patient with meningitis contains Gram-negative cocci, many in pairs. Which organism below is most likely?

A.


B.


C.


D.

Pseudomonas aeruginosa

E.

Escherichia coli

16.

After Gram stain of spinal fluid sample from a patient with meningitis Medical personal during microscopy examination detected Gram-negative cocci, many in pairs. Which organism below is most likely?

A.


B.


C.


D.


E.

Escherichia coli

17.

Which test below would best distinguish S. aureus from one of the less-virulent staphylococci?

A.

Production of catalase.

B.

Colony color when grown on BHI agar.

C.

Ability to grow on MacConkey agar.

D.

*Production of coagulase.

E.

Type of hemolysis on sheep blood agar.

18.

How we can distinguish S. aureus from staphylococci epidermidis?

A.


B.


C.


D.


E.


19.

The laboratory informs you that an isolate of Staphylococcus aureus is ‘methicillin-resistant’. Which phrase below best describes such isolates?

A.

Although resistant to methicillin, nearly all are sensitive to cephalosporins.

B.

*They are resistant to both ‘anti-staph’ penicillins and cephalosporins.

C.

They are seldom resistant to antibiotics other than ?-lactams.

D.

They produce a ?-lactamase active on both cephalosporins and penicillins.

E.

The ‘methicillin-resistance’ gene also confers resistance to vancomycin.

20.

A young man has a large pus-filled abscess on his upper arm but does not go to a doctor. Several days later he is brought to the Emergency Room with fever, hypotension, and multiple organ failure. Which of the following is most likely to be responsible?

A.

Streptococcus pyogenes Erythrogenic toxin.

B.

Clostridium perfringens ?-toxin.

C.

*Staphylococcus aureus Toxic Shock Syndrome Toxin-1.

D.

Shigella dysenteriae Shiga Toxin.

E.

Escherichia coli Heat-labile Toxin (ST).

21.

Members of a family suffer acute attacks of nausea and vomiting a few hours after returning from a daylong picnic, at which they ate hamburgers, potato salad, and custard pie. By morning all are feeling better. Which bacterial toxin is most likely to have caused their symptoms?

A.

Clostridium difficile Cytotoxin.

B.

Escherichia coli Labile Toxin

C.

Escherichia coli Stable Toxin.

D.

*Staphylococcus aureus Enterotoxin.

E.

Helicobacteri pylori Cytotoxin.

22.

Five young men suffer acute attacks of nausea and vomiting a few hours after returning from a student’s party, at which they ate hamburgers, potato salad, and custard pie. By morning all are feeling better.

Which bacterial toxin is most likely to have caused their symptoms?

A.


B.


C.


D.


E.


23.

E. coli and Neisseria meningitidis isolated from blood cultures often have transport systems (for acquiring metal ions from the environment) lacking in their less-virulent relatives. Which metal is acquired by the majority of these systems?

A.

Copper

B.

Sodium

C.

Potassium

D.

Magnesium

E.

*Iron

24.

A 25-year-old woman presents with a swollen, warm, painful knee. Aspirated joint fluid is cloudy and when cultured on chocolate agar gives rise to oxidase-positive colonies of Gram-negative diplococci.

Which bacterium is most likely to be the cause of this infection?

A.


B.

Staphylococcus aureus

C.


D.

*Neisseria gonorrhoeae

E.

Nocardia asteroides

25.

In cervical specimens of 21-year-old woman presents gram-negative diplococci within leucocytes.


A.


B.


C.


D.


E.

Nocardia asteroides

26.

A workman has a large pus-filled lesion on the left forearm, tender, red, and swollen. It is incised. A smear of the pus is Gram-stained. Many neutrophils are seen, also many Gram-positive cocci, most in large clusters. The organism is b-hemolytic on sheep blood agar. Colonies are pale-yellow, opaque, and shiny, with neat round outlines. Of the bacteria listed below, which is most likely to have produced the abscess?

A.

Streptococcus bovis

B.


C.

Streptococcus mitis

D.


E.


27.

A young man complaines on pain on urination and profuse purulent discharge from his urethra. Gram stain of the discharge revealed large numbers Gram-negative cocci, mostly in pairs within neutrophils.

Which bacterium is most likely to have caused his infection?

A.

Mycoplasma hominis

B.

Chlamydia trachomatis

C.


D.

Ureaplasma urealyticum

E.

Treponema pallidum

28.

A 17-year-old sexually-active male presents with a four-day history of pain on urination and profuse purulent discharge from his urethral opening. Gram stain of the discharge revealed large numbers of neutrophils. A small fraction of neutrophils contained Gram-negative cocci, mostly in pairs. Which bacterium is most likely to have caused his infection?

A.

Mycoplasma hominis

B.


C.

Treponema pallidum

D.


E.


29.

An 18-year-old high school student has a large pus-filled lesion on the left forearm, tender, red, and swollen. It is incised, drained, washed, and bandaged. A smear of the pus is Gram-stained. Many neutrophils are seen, also many Gram-positive cocci, most in large clusters. The organism is bhemolytic on sheep blood agar. Colonies are pale-yellow, opaque, and shiny, with neat round outlines.

Of the bacteria listed below, which is most likely to have produced the abscess?

A.


B.


C.

Streptococcus mitis

D.


E.

Streptococcus bovis

30.

Heavily-encapsulated strains of Neisseria meningitidis are far more virulent than non-encapsulated isolates. How does a capsule enhance virulence?

A.

Binds to the Fc region of some subclasses of human IgG.

B.

Prevents activation of complement by the classical pathway.

C.

Enables bacteria to adhere tightly to mammalian cells.

D.

Reduces access of antibiotics to the bacterial membrane.

E.

*Inhibits phagocytosis by neutrophils

31.

A post-surgical patient develops fever and there is redness and swelling around the surgical incision. A day later pus begins to flow from the incision; Gram stain of pus shows large numbers of neutrophils and many Gram-positive cocci, some in clusters. The organism is beta-hemolytic on blood agar, and is coagulase- and catalase-positive. Which organism is most likely?

A.


B.


C.

Streptococcus pyogenes (Group A)

D.

Streptococcus agalactiae (Group B)

E.


32.

A beta-hemolytic streptococcus is isolated from an infected neonate. Such isolates are often members of

Lancefield Group B. The antigenic structure of which bacterial component defines Lancefield Groups?

A.

Capsule polysaccharide.

B.

*Cell-associated or C-carbohydrate.

C.

Wall and membrane teichoic acids.

D.

Beta-hemolysins.

E.

Filamentous proteins of the cell envelope.

33.

In the immune response to invasive infections by Streptococcus pneumoniae, antibodies are required for effective defense. Antibodies to which antigen are most important?

A.

Teichoic acid.

B.

Peptidoglycan.

C.

C-carbohydrate.

D.

Type III secretion system.

E.

*Polysaccharide capsule.

34.

The main carrier site on the human body for strains of potentially pathogenic Staphylococcus aureus is the

A.

oral cavity

B.

*throat (posterior nasopharynx)

C.

nasal membranes

D.

gastrointestinal tract

E.

vagina

35.

The carrier site in humans for pathogenic Neisseria meningitidis is the

A.

Conjunctiva

B.

*nasopharynx

C.

urogenital tract

D.

blood

E.

meninges

36.

Silver nitrate or an antibiotic is put into the eyes of newborn infants to prevent infection by

A.

Doderlein's bacillus (Lactobacillus acidophilus)

B.

Herpes simplex virus

C.


D.

Chlamydia trachcomatis

E.

two of the above

37.

A characteristic of Streptococcus mutans that allows it to initiate dental plaque and dental caries is:

A.

the ability to attach specifically to the pellicle of the tooth

B.

the ability to utilize sucrose as a source of carbon and energy

C.

the ability to produce a dextran capsule

D.

* the ability to produce lactic acid

E.

all are true

38.

The fibrin coat that can be formed by coagulase-positive staphylococci and the hyaluronic acid capsule of Streptococcus pyogenes are pathogenic strategies to

A.

promote colonization of a host

B.

cause direct damage to host cells during pathogenesis

C.

hide bacterial antigens from the host immune tissues

D.

*survive as intracellular parasites

E.

alter or change their surface antigens within the course of an infection

39.

Leukocidins are

A.

enzymes contained in the lysosomes of phagocytes to kill ingested bacteria

B.

proteins produced by bacteria that kill closely-related bacteria

C.

proteases produced by bacteria which destroy host immunoglobulins

D.

enterotoxins produced by Staphylococcus aureus involved in food-borne disease

E.

* substances produced by pyogenic bacteria that kill phagocytes

40.

The streptococcal invasin which behaves as a "spreading factor" by breaking down the framework of connective tissues is called

A.

Collagenase

B.

Streptokinase

C.

Streptolysin

D.

erythrogenic toxin (pyogenic exotoxin)

E.

* hyaluronidase

41.

A primary determinant of virulence in Streptococcus pyogenes, which is involved in adherence, resistance to phagocytosis and antigenic variation, is

A.

Streptokinase

B.

lipopolysaccharide (endotoxin)

C.

*M-protein

D.

Protein A

E.

coagulase

42.

The similarity between the toxic shock syndrome toxin (TSST), the staph enterotoxins, and the erythrogenic toxin (pyogenic exotoxin) is

A.

they are all produced by Staphylococcus aureus

B.

*they stimulate the immune system in a similar manner as superantigens

C.

the pathology of the diseases that they cause is identical

D.

they are all neurotoxins

E.

they are the same (identical) toxin produced by three different organisms

43.

The main carrier site on the human body for strains of potentially pathogenic Neisseria meningitidis is the

A.

nasal membranes

B.

* throat (posterior nasopharynx)

C.

oral cavity

D.


E.

vagina

44.

Characteristics of Streptococcus mutans which allow it to initiate dental caries include

A.


B.

*the ability to produce lactic acid from sucrose, glucose and fructose

C.

the ability to form and grow in a biofilm on the enamel of the tooth

D.

all are true

E.

all are false

45.

A determinant of virulence of Streptococcus pneumoniae which allows the bacteria to resist engulfment by phagocytes is

A.

fimbriae

B.

*a polysaccharide capsule

C.

production of TSST exotoxin

D.

coagulase

E.

neuraminidase

46.

The fimbriae of pathogenic Neisseria gonorrhoeae are apparently essential to the bacterium when it produces the disease gonorrhea because

A.

*they are responsible for initial attachment of the bacteria to the urethral or cervical epithelium

B.

they cause the production of pus which is characteristic of gonorrhoea

C.

they make the bacteria resistant to phagocytic killing and digestion by white blood cells

D.

they convert urinary tract components (urine) to substances which provoke symptoms of disease

E.

they allow the bacteria to swim "upstream" against the flow of urine and thereby remain established in the urinary tract

47.

Which bacterial invasin is mismatched with its activity in the host?

A.

staphylokinase: degrades fibrin

B.

coagulase: clots fibrin

C.

*hyaluronidase: degrades the ground substance of connective tissue

D.

streptolysin: lyses neutrophil membranes

E.

all are false

48.


A.

promote colonization of a host

B.


C.


D.

*survive as intracellular parasites

E.

alter or change their surface antigens during the course of an infection

49.

What bacterial structure or substance is primarily associated with antigenic variation in the Group A streptococci?

A.

outer membrane protein (omp)

B.

streptokinase

C.

hyaluronic acid capsule

D.

*Polysaccharide

E.

M-protein

50.

Which of the following bacterial toxins behaves as a superantigen through its stimulation of a very large fraction of the host T-cell population?

A.

Streptococcal streptolysin

B.

Salmonella LPS (endotoxin)

C.

Pseudomonas Exotoxin A

D.

*Staphylococcal toxic shock syndrome toxin

E.

E. coli O157 H:7 shiga toxin

51.

Scalded skin syndrome is due to which toxin of Staphylococcus aureus?

A.

*Epidermolytic toxin.

B.

Enterotoxin.

C.

Leucocidin.

D.

Haemolysin

E.

Necrotoxin

52.

Isolation of pneumococci from clinical specimens may be attempted by intraperitoneal inoculation

A.

rabbits.

B.

rats.

C.

*mice.

D.

sheep.

E.

Mice

53.

Which of the following organisms may lead to pseudomembrane formation in the throat?

A.

Corynebaclerium diphtheriae

B.

Treponema Vinsentii

C.

Streptococcus pyogenes.

D.

Candida albicans.

E.

*All are true

54.

Most strains of Staphylococcus aureus show:

A.

*a golden-yellow pigment.

B.

?-haemolysis on sheep blood agar.

C.

phosphatase production.

D.

novobicin resistance

E.

all are true.

55.

A positive Schick test implies that the person is:

A.

immune and non-hypersensitive.

B.

*susceptible and non-hypersensitive.

C.

immune and hypersensitive.

D.

non-immune and hypersensitive.

E.

healthy

56.

Which of the following agents is the commonest cause of infective endocarditis?

A.

Staphylococcus epidermidis.

B.

Candida spp.

C.

*Viridans group of streptococci.

D.

Coliforms.

E.

Rickettsia

57.

Which of the following bacteria ferment mannitol anaerobically?

A.

*Staphylococcus aureus.

B.

S. epidermidis.

C.

S. saprophyticus.

D.

S. canis

E.

All are true.

58.

70. Which of the following are pyogenic cocci:

A.

Streptococcus

B.

Staphylococcus

C.

Pneumococcus

D.

Neisseria

E.

*all are true

59.

The coagulase test is used to differentiate Staphylococcus aureus from

A.

other staphylococci

B.

*streptococci

C.

micrococci

D.

enterococci

E.

pneumococci

60.

The symptoms in scarlet fever are due to

A.

streptolysin

B.

coagulase

C.

*pyrogenic toxin

D.

alpha toxin

E.

leucocidin

61.

Penicillin-resistant Staphylococcus can be treated with ______ without sensitivity testing.

A.

ampicillin

B.

erythromycin

C.

methicillin

D.

amoxycillin

E.

*no antibiotic

62.

The most severe streptococcal diseases are caused by

A.

*group A streptococci

B.

group B streptococci

C.

group C streptococci

D.

pneumococci

E.

enterococci

63.

Rheumatic fever damages the _______, and glomerulonephritis damages the______

A.

skin, heart

B.

joints, bone marrow

C.

*heart valves, kidney

D.

brain, kidney

E.

heart, bone marrow

64.

______ hemolysis is the partial lysis of red blood cells due to bacterial hemolysins.

A.

* Alpha

B.

Beta

C.

Gamma

D.

Delta

E.

Epsilon

65.

An effective vaccine exists to prevent infections from

A.


B.


C.

Neisseria gonorrhoeae

D.

*Streptococcus pneumoniae

E.

Streptococcus epidermidis

66.

Viridans streptococci commonly cause

A.

pneumonia

B.

meningitis

C.

*subacute endocarditis

D.

otitis media

E.

arthritis

67.

Which genus of bacteria has pathogens that can cause blindness and deafness?

A.

Branhamella

B.

Staphylococcus

C.

Streptococcus

D.

*Neisseria

E.

Shigella

68.

An important test for identifying Neisseria is

A.

*production of oxidase

B.

production of catalase

C.

sugar fermentation

D.

beta-hemolysis

E.

alfa- hemolysis

69.

A complication of genital gonorrhea in both men and women is

A.

*infertility

B.

pelvic inflammatory disease

C.

arthritis

D.

blindness

E.

E. urethritis

70.

The skin blotches in meningitis are due to

A.

blood clots

B.

*endotoxins in the blood

C.

erysipelas

D.

exotoxin in skin

E.

E. skin invasion by N. meningitidis

71.

Which infectious agent of those covered in the chapter would most likely be acquired from a contaminated doorknob?

A.


B.


C.

Neisseria meningitidis

D.


E.


72.

A child develops pneumonia. The bacterium Streptococcus pneumoniae is cultured from the patient’s sputum. Cells of the cultured bacteria have thick polysaccharide capsules. How did the presence of capsules promote development of serious disease?

A.

Prevented binding of antibodies to the bacteria.

B.

Prevented initiation of a humoral immune response.

C.

Prevented activation of helper T cells.

D.

*Prevented phagocytosis by neutrophils.

E.

Prevented mast-cell degranulation.

73.

An elderly man develops pneumonia and septicemia. Gram stain of sputum contains many neutrophils and Gram-positive cocci, in pairs. Blood and sputum cultures grow out a Gram-positive coccus, ?hemolytic on sheep blood agar, and catalase-negative. Which organism below is most likely?

A.


B.

Staphylococcus aureus.

C.

*Streptococcus pneumoniae.

D.


E.

Streptococcus agalactiae.

74.

Staphylococcus aureus is easily transmitted within the hospital environment. Which feature of this bacterium is most largely responsible for its ease of spread?

A.

*Resistance to heat, cold, and drying.

B.

Ability to colonize the digestive tract.

C.

Presence of an outer membrane impermeable to most disinfectants.

D.

Production of extracellular polysaccharide which allows it to adhere tightly to surfaces.

E.

Ability to form spores which are resistant to disinfectants and easily dispersed.

75.

A 23-year-old medical student had headache and fever one evening. By the next morning she had become very ill, with high fever, severe headache, and stiff neck. She was admitted to the hospital. Later that day she developed rash, at first petechial and then pupuric. Gram stain of CSF showed many white cells and Gram-negative cocci, many in pairs. Which organism is most likely to be the cause of her infection?

A.

Escherichia coli.

B.

Haemophilus influenzae.

C.

*Neisseria meningitidis.

D.


E.

Streptococcus pneumoniae.

76.

A patient has cellulitis of the left arm, persistent fever, and a heart murmur. He is a habitual user of illegal drugs, which he self-administers intravenously. An echocardiogram shows a bacterial vegetation on the aortic valve. Three blood cultures all grow an ?-hemolytic Gram-positive coccus, catalasenegative. Which organism is most likely to have caused his infection?

A.


B.

*A Viridans-group Streptococcus.

C.

Streptococcus pyogenes [Group A].

D.

Streptococcus agalactiae [Group B].

E.

Streptococcus bovis [Group D].

77.

Untreated pharyngitis produced by Group A streptococci can result in later development of Acute rheumatic fever, created by cross-reaction of anti-streptococcal antibodies with heart tissue. Which streptococcal antigen stimulates formation of these cross-reactive antibodies?

A.

A.Group A carbohydrate.

B.

Flagella.

C.

*M protein

D.

Peptidoglycan.

E.

Teichoic acid.

78.

A neonate develops septicemia. Blood cultures produce a ?-hemolytic Gram-positive coccus. It is catalase negative. Which test would best confirm the identity of the pathogen as a Group B

Streptococcus?

A.

*Synergy of hemolysin with the hemolysin of Staphylococcus aureus [CAMP test].

B.

Bile-esculin test.

C.

Bacitracin sensitivity.

D.

Optochin sensitivity.

E.

Novobiocin sensitivity.

79.

A individual may have repeated infections with Neisseria gonorrhoeae, despite the fact that each infection gives rise to an immune response. By which mechanism does the gonococcus evade protective immunity?

A.

Thick capsule prevents binding of antibodies to the cell surface.

B.

Pili adhere to epithelial cells despite binding of antibodies.

C.

Capsular polysaccharide is identical to polysaccharides of mammalian cells.

D.

Outer membrane lacks any antigenic components.

E.

*The surface antigens present change continually, as a result of pre-programmed changes in

DNA.

80.

An elderly resident of a nursing home develops pneumococcal pneumonia. This illness might have been prevented had the patient been immunized against this organism. Which antigens of S. pneumoniae are included in the adult vaccine?

A.

M-proteins.

B.

Intact heat-killed bacteria.

C.

Toxoids produced from superantigen toxins.

D.

*Capsular polysaccharides.

E.

Cell-associated (C) carbohydrates.

81.

Before the advent of immunization, outbreaks of meningococcal disease were frequent in military camps. A factor in development of such outbreaks is the ability of Neisseria meningitidis to establish an asymptomatic ‘carrier state’. What is the predominant site of carriage of Neisseria?

A.

Urethral epithelium.

B.

Gall bladder.

C.

Large intestine.

D.

*Nasopharynx.

E.

Meninges and choroid plexus

82.

A patient develops pneumonia caused by Streptococcus pneumoniae. The predominant virulence factor of this organism is a thick capsule . Which phrase best describes the role of this capsule in virulence?

A.

Aids in acquisition of iron.

B.

Toxic to lung epithelial cells

C.

Identical to human polysaccharide, so is non-immunogenic.

D.

*Reduces phagocytosis by neutrophils.

E.

Inhibits activation of Complement.

83.

Which of the following statements best describes Streptococcus pneumoniae?

A.

*bile soluble, optochin sensitive, capsulated

B.

bile soluble, catalase negative, noncapsulated

C.

bile soluble, gramnegative, optochin resistant

D.

bile soluble, catalase positive, optochin sensitive

E.

bile soluble, catalase negative, motily

84.

Which of the following is a pathogen of the oropharynx?

A.


B.

*Streptococcus pyogenes

C.

Streptococcus bovis

D.

Streptococcus viridans

E.


85.

What do endotoxins and exotoxins have in common?

A.

secreted into the medium

B.

*cause damage to the host

C.

heat stable

D.

heat resistent

E.

contain polysaccharide

86.

Which virulence factor results in the symptoms of Staphylococcal food poisoning?

A.

exfoliative exotoxin

B.

hyaluronidase

C.

endotoxin

D.

*enterotoxin

E.

neurotoxin

87.

Which of the following best describes the pathogenesis of acute rheumatic fever?

A.

*characterized by inflammation of the heart and/or the joints

B.

due to an immunologic cross reaction between heart muscle and Staphylococcus aureus

C.

involves B-hemolytic Streptococci growing in the heart

D.

is a complication of Group A Streptococcal skin disease as well as pharyngitis

E.

tonsilitis is first stage of development of rheumatic fever

88.

Which of the following statements about gonorrhea is true?

A.

Men are frequently asymptomatic carriers.

B.

Bacteremia is common.

C.

Serologic diagnosis is more reliable than culture.

D.

Penicillins are no longer recommended for treatment.

E.

*Gonococci are within leucocytes in a sample

89.

Which test result would rule out an Enterococcus isolate?

A.

growth in 6.5% NaCl

B.

*oxidase positive

C.

catalase negative

D.

PYR positive

E.

motility

90.

What is the most common cause of urinary tract infections?

A.

Staphylococcus saprophyticus

B.

Escherichia coli

C.

*Enterococcus fecalis

D.

Streptococcus bovis

E.


91.

Which of the following is NOT true of Neisseria gonorrhea?

A.

Is a mucosal pathogen

B.

*Requires a vaginal pH of 5 or more to grow

C.

Can disseminate in the immunosuppressed

D.

Complications include ectopic pregnancy, PID and sterility

E.

Gram-negative diplococci

92.

Which of the following is NOT true of Neisseria meningitidis?

A.

Crosses the blood brain barrier

B.

*Has 3 serotypes - A, B, Y

C.

Colonizes nasopharynx

D.

Predisposed groups include diabetics

E.

Has peptidoglycan

93.


A.

Colon

B.

*Nose

C.

Throat

D.

Vagina

E.

All are true

94.


A.


B.


C.


D.


E.

All are true

95.


A.


B.

*Enterococcus faecalis

C.

Escherichia coli

D.

Vibrio cholerae

E.

All are true

96.

Your patient is a 30-year-old woman with nonbloody diarrhea for the past 14 hours. Which one of the following organisms is LEAST likely to cause this illness?

A.

Clostridium difficile

B.


C.

Shigella dysenteriae

D.

Salmonella enteritidis

E.

All are true

97.

Your patient has subacute bacterial endocarditis caused by a member of the viridans group of streptococci. Which one of the following sites is MOST likely to be the source of the organism?

A.

Skin

B.

Colon

C.

*Oropharynx

D.

Urethra '

E.

All are true

98.

A culture of skin lesions from a patient with pyoderma (impetigo) shows numerous colonies surrounded by a zone of beta hemolysis on a blood agar plate. A Gram-stained smear shows gram-positive cocci. If you found the catalase test to be negative, which one of the following organisms would you MOST probably have isolated?

A.


B.


C.


D.


E.

All are true

99.

The coagulase test, in which the bacteria cause plasma to clot, is used to distinguish

A.

Streptococcus pyogenes from Enterococcus faecalis

B.

Streptococcus pyogenes from Staphylococcus aureus

C.

*Staphylococcus aureus from Staphylococcus epidermidis

100.

D. Staphylococcus epidermidis from Neisseria meningitidis

F.

All are true

101.

Which one of the following is considered a virulence factor for Staphylococcus aureus?

102.

A.

A heat-labile toxin that inhibits glycine release at the internuncial neuron

B.

An oxygen-labile hemolysin

C.

Resistance to novobiocin

D.

*Protein A that binds to the Fc portion of IgG

E.

All are true

Each of the following statements concerning Staphylococcus aureus is correct EXCEPT:

A.

Gram-positive cocci in grapelike clusters are seen on Gram-stained smear

B.

The coagulase test is positive

C.

Treatment should include a (3-lactamase-resistant penicillin

D.

*Endotoxin is an important pathogenetic factor

103.

E.

All are true

Two hours after a delicious Thanksgiving dinner of barley soup, roast turkey, stuffing, sweet potato, green beans, cranberry sauce, and pump kin pie topped with whipped cream, the Smith family of four experience vomiting and diarrhea. Which one of the following organisms is MOST likely to cause these symptoms?

A.

Shigella flexneri

B.

Campylobacter jejuni

C.


D.


E.

All are true

104.

105.

The MOST important contribution of the capsule of Streptococcus pneumoniae to virulence is

A.

To prevent dehydration of the organisms on mucosal surfaces

B.

*To retard phagocytosis by polymorphonuclear leukocytes

C.

To inhibit polymorphonuclear leukocyte chemo taxis

D.

To accelerate tissue invasion by its collage-naselike activity

E.

All are true

The MOST important way the host circumvents the function of the pneumococcal

106.

polysaccharide capsule is via

A.

T lymphocytes sensitized to polysaccharide antigens

B.

Polysaccharide-degrading enzymes

C.

*Anticapsular antibody

D.

Activated macrophages

E.

All are true

Each of the following statements concerning staphylococci is correct EXCEPT:

A.

S. aureus is differentiated from S. epidermidis by the production of coagulase

B.

S. aureus infections are often associated with abscess formation

C.

The majority of clinical isolates of S. aureus elaborate penicillinase; therefore, presumptive antibiotic therapy for S. aureus infections should not consist of penicillin G

D.

*Scalded skin syndrome caused by S. aureus is due to enzymatic degradation of epidermal desmosomes by catalase

107.

E.

All are true

Regarding the effect of benzylpenicillin (penicillin G) on bacteria, which one of the following organisms is LEAST likely to be resistant?

A.


B.


C.


D.


108.

E.

All are true

Which one of the following is NOT an important characteristic of either Neisseria gonorrhoeae or Neisseria meningitidis?

A.

Polysaccharide capsule

B.

IgA protease

C.

*M protein

D.

Pili

109.

E.

All are true

Which one of the following is NOT an important characteristic of Streptococcus pyogenes?

A.

*Protein A

B.

M protein

C.

Beta-hemolysin

D.

Polysaccharide group-specific substance

E.

All are true

110.

Three organisms, Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae cause the vast majority of cases of bacterial meningitis. What is the MOST important pathogenic component they share?

A.

Protein A

B.

*Capsule

C.

Endotoxin

D.

beta-Lactamase

E.

All are true

111.

Tissue-degrading enzymes play an important role in the pathogenesis of several bacteria. Which one of the following is NOT involved in tissue or cell damage?

A.

Lecithinase of Clostridium perfringens

B.

Hyaluronidase of Streptococcus pyogenes

C.

*M protein of Streptococcus pneumoniae

112.

113.

D.

Leukocidinof Staphylococcus aureus

E.

All are true

Of the organisms listed below, which one is the MOST frequent bacterial cause of pharyngitis?

A.


B.


C.


D.


E.

All are true

Each of the following statements concerning gonorrhea is correct EXCEPT:

A.

Infection in men is more frequently symptomatic tY\an in women

B.

A presumptive diagnosis can be made by finding gram-negative kidney-bean-shaped diplococci within neutrophils in a urethral discharge

114.

C.

*The definitive diagnosis can be made by detecting at least a 4-fold rise in antibody to Neisseria gonorrhoeae

D.

Gonococcal conjunctivitis of the newborn rarely occurs in the United States, because silver nitrate or erythromycin is commonly used as prophylaxis

E.

All are true

Each of the following statements concerning neisseriae is correct EXCEPT:

A.

They are gram-negative diplococci

B.

They produce IgA protease as a virulence factor

C.

They are oxidase-positive

115.

D.

*They grow best under anaerobic conditions

E.

All are true

Each of the following statements concerning Neisseria meningitidis is correct EXCEPT:

A.

It is an oxidase-positive, gram-negative diplo-coccus

B.

It contains endotoxin in its cell wall

C.

*It produces an exotoxin that stimulates adenylate cyclase

D.

It has a polysaccharide capsule that is antiphagocytic

E.

All are true

Which organism below, if present in only one of three blood cultures from a single patient, is 116.

most likely to represent contamination caused by poor antiseptic technique, rather than genuine infection?

A.

*Staphylococcus epidermidis.

B.


C.

Escherichia coli.

D.

Pseudomonas aeruginosa.

E.


117.

An 81-year-old man with chronic emphysemea and hypertension develops fever, chills, and respiratory distress. X-rays show lobar pneumonia. Sputum smear contains numerous Gram-positive cocci, many of which are in pairs. Sputum culture on Sheep blood agar produces many colonies of an alpha-hemolytic Gram-positive coccus. It is catalase-negative, Bile-esculin negative, and optochinsensitive. Which of the organisms below is most likely?

A.


B.


C.

Streptococcus mitis

D.

Streptococcus bovis (Group D)

E.


118.

A post-surgical patient develops redness around the incision and a day later pus begins to ooze from the wound. Culture of a swab of pus produces beta-hemolytic colonies on Sheep blood agar. Gram stain shows that the bacteria are Gram-positive cocci. Catalase and coagulase tests are positive. Which

119.

of the following organisms is most likely?

A.


B.


C.

Streptococcus mitis

D.


E.


A 75-year-old man reports malaise, headache, and fever. On examination his neck is stiff. Gram stain of CSF reveals neutrophils and numerous Gram-negative cocci, many in pairs.Which organism below is most likely?

A.


B.

Klebsiella pneumoniae

C.


D.


E.


120.

A 19-year-old man comes to your clinic because of thick purulent discharge from the urethral opening of his penis. On Gram-stain of the discharge huge numbers of neutrophils are seen, a few of which contain intracellular Gram-negative cocci. Many of the cocci are in pairs. What is the most likely

121.

organism?

A.

Neisseria meningitidis.

B.

*Neisseria gonorrhoeae.

C.

Haemophilus ducreyi.

D.

Mycoplasma hominis.

E.

Treponema pallidum.

What is the most common outcome of infection with Helicobacter pylori?

A.

Severe diarrhea

B.

No clinical manifestations

C.

Bacteremia

D.

Hepatitis

122.

E.

*Peptic ulcers or gastric cancer

A 35-year old patient got fever, nausea, vomiting and bloody diarrhea, all of the following

123.

bacteria should be considered in the diffrential diagnosis, except one:

A.

Salmonella

B.

ETEC

C.

Shigella

D.

Yersinia

E.

*Campylobacter

A 38 years old patient has chronic gastritis. Which of the following organisms is most likely?

A.

Campylobacter fetus.

B.

Escherichia coli.

C.

A non-cholera Vibrio.

D.

Campylobacter jejuni.

E.

*Helicobacter pylori.

124.

lesion?

A 40-years-old patient has a peptic ulcer. Which organism is most likely to have created this

A.


B.

Enterococcus faecalis.

C.

Escherichia coli.

D.


E.

*Helicobacter pylori

125.

A 5-years-old girl develops bloody diarrhea, produced by Shigella infection. From which source was this infection most likely to have been contracted?

A.

Rare hamburger.

B.

Dog or cat.

C.

Spores present in soil.

126.

D.

Cow, horse, or sheep.

E.

*Another child.

A 6-year-old boy was brought to the emergency room with a history of bloody diarrhea over the preceding two days. A fecal smear contained numerous red cells and neutrophils. Stool culture on Endo agar produced lactose-negative colonies amid colonies of ‘normal intestinal flora’. Which of the organisms below is most likely to be the cause of his illness?

A.

Enteropathogenic E. coli

B.

Balantidium coli.

C.

Entamoeba histolytica

D.

Giardia lamblia.

127.

E.

*Shigella.

A few healthy adult travelers visiting Peru are cautioned against eating uncooked vegetables and unpeeled fruits, and against drinking unbottled water. However, they are already resistant to cholera

128.

because of:

A.

the gamma globulin shots they received before their trip.

B.

their ability to avoid contaminated food due to its acidic smell.

C.

they were vaccinated

D.

their consumption of large prophylactic amounts of bicarbonates.

E.

*a gastric barrier, due to stomach acids.

A four-year-old boy was brought to the emergency room with a history of bloody diarrhea over the preceding two days. A fecal smear contained numerous red cells and neutrophils. Stool culture on

Endo agar produced lactose-negative colonies amid colonies of ‘normal intestinal flora’. Which of the organisms below is most likely to be the cause of his illness?

A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

129.

E.

*Shigella.



A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

130.

E.

*Shigella.

A laboratory got a sample from a patient with cholera. Which of the following tests would not differentiate Vibrio cholera non O1 from Vibrio parahaemolyticus?

A.

oxidase activity.

B.

Growth on special blood agar

C.

Production of enterotoxin

D.

Growth on salt-free and salt-containing agar.

E.

*Growth on TCBS agar

131.

A laboratory got a sample from a patient with cholera. Which of the following is not true about the bacterium classified as Vibrio cholerae (V. cholerae О1):

A.

causes disease only through the production of an enterotoxin

B.

reacts with group 1 antiserum against the lipopolysaccharide (О) antigens

C.

arabinose is not fermented

D.

invades the small intestine

E.

*is often associated with marine environments

132.

A laboratory got a sample from a patient with diarrhoea. Which of the following media is an enrichment medium for the isolation of Shigella?

A.

Tetrathionate broth.

B.

Alkaline peptone water.

C.

Taurocholate peptone transport and enrichment medium.

133.

D.

Endo medium

E.

*Selenite broth.

A laboratory got a sample from a patient with diarrhoea. Cholera toxin resembles which of the

134.

following toxins?

A.

Stable toxin of E. coli.

B.

Diphtheria toxin.

C.

Tetanus toxin.

D.

Staphylococcus enterotoxin

E.

*Labile toxin of Escherichia coli.

A laboratory got a sample from a patient with diarrhoea. To test a stool specimen for

135.

Campylobacter, all of the following measures would be used except:

A.

Plating on agar containing glucose or sucrose

B.

Plating on Campy blood agar containing 5 antibiotics

C.

Incubating the plates in an atmosphere of 5% O2, 10% CO2

D.

Incubating the plates at 42° C

E.

*Passing the samples through 0.45 micron filters

A laboratory got a sample from a patient with diarrhoea. Shigella is transmitted by

A.

ticks

B.

direct contact

C.

air dropled

D.

louse

E.

*infected food and water

136.

A laboratory got a sample from a patient with diarrhea. The severe diarrhea of cholera is produced by a protein exotoxin that acts on enterocytes. Which statement below best describes the effect of Cholera toxin?

A.

Alters the actin cytoskeleton.

B.

Inactivates ribosomes.

C.

Stimulates guanyl cyclase.

D.

Proteolytic cleavage of a specific cellular protein.

E.

*Stimulates adenyl cyclase.

137.

A laboratory got a specimen from a patient with cholera. The following occurs during the course of disease due to Vibrio cholerae infection, except one:

A.

Patients experience nausea, vomiting, abdominal cramping, and diarrhea.

B.

Patients sometimes lose between 10 to 20 liters of fluid/day.

C.

“Rice-water” stool presents

D.

Patients show signs of disease at 8 to 72 hrs after ingestion of contaminated food or water.

138.

E.

*Patients sustain considerable damage to their intestines.

A man, 38 y.o. has gastritis. The pathogenic mechanisms that make Helicobacter pylori the causative agent of gastritis include the following except:

A.

urease production

B.

catalase production

C.

microaerophilism

D.

motility

E.

*invasive abilities

139.

A microbiologist got a sample from a patient with cholera. Which of the following statements is true about the toxin produced by Vibrio cholera?

A.

The B subunit directly stimulates the host adenylate cyclase.

B.

The toxin blocks the host adenylate cyclase.

C.

The toxin is lypopolisaccharide

D.

It has its own adenylate cyclase activity.

E.

*The A1 subunit indirectly stimulates the host adenylate cyclase.

140.

A microbiologist got a specimen from a patient with cholera. To determine to which species of vibrios infectious agent belongs, the microbiologist performs some tests on colonies cultured from stool samples. These tests include the following EXCEPT:

A.

growth on thiosulfate-citrate-bile-sucrose (TCBS) agar

B.

fermentation of sucrose

C.

phagotyping

D.

growth at different NaCl concentrations

E.

*serotyping based on H antigens

141.

A middle aged man recently returned from visiting his family in India develops severe diarrhea.

He in fact has cholera. His diarrhea is produced by a protein exotoxin secreted by Vibrio cholerae. How does this toxin act?

A.

ADP-ribosylates a chloride transporter.

B.


C.

Inhibits guanyl cyclase.

D.

Inhibits a G protein that inhibits adenyl cyclase.

142.

E.

*Stimulates a G protein that activates adenyl cyclase.

A motive not to administer beta lactam antibiotics for a Gram-negative septicemia, unless there is no other alternative, is

A.

the lysis of bacterial cells increases the activity of bacterial LPS

B.

Complement activation cannot occur in the presence of the antibiotic

C.

the antibiotic suppresses the immune response necessary to eliminate the pathogen

D.

the antibiotic eliminates the normal flora

143.

E.

*beta lactam antibiotics are ineffective against Gram-negative bacteria

A patient got diarrhoea. The pathogenesis of which one of the following organisms is MOST likely to involve invasion of the intestinal mucosa?

A.

Enterotoxigenic Escherichia coli

B.

Clostridium botulinum

C.

Enteropathogenic Escherichia coli

D.

Vibrio cholerae

144.

E.

*Shigella sonnei

A patient got severe diarrhoea. If this patient had Shigellosis, the stool culture on MacConkey agar will grow:

A.

glucose fermenting colonies

B.

pink colonies

C.

black colonies

D.

lactose fermenting colonies

145.

E.

*non-lactose fermenting colonies

A patient has a peptic ulcer. Which organism is most likely to have created this lesion?

A.


B.


C.


D.

Escherichia coli.

146.

E.


A patient has been diagnosed with a gastric ulcer. A test of the patient's serum shows reactivity with Helicobacter pylori antigens. Which of the following is true?

A.

The patient's gastrin-hydrochloric homeostasis has been maintained.

B.

Damage to the patient's gastric mucosa has been primarily caused by the patient's own immune response.

C.

All are true

D.

The Helicobacter pylori infection most likely has nothing to do with the patient's condition.

E.

*The patient will be treated with amoxicillin to eradicate H. pylori colonization and eliminate its recurrence.

147.

148.

149.

A patient has chronic gastritis. Which of the following organisms is most likely?

A.

Escherichia coli.

B.


C.


D.


E.


A person got cholera. The best treatment for cholera is

A.

tetracycline

B.

toxoid

C.

vaccine

D.

antiserum injection

E.

*rehydration therapy

A person got cholera. The large volume of fluid lost by diarrhea during infection with Vibrio cholerae

A.

is a consequence of fluid replacement during treatment of the disease and does not result directly from activity of the cholera toxin

B.

results from electrolytes binding to the intestinal enterocytes which upsets their water retention capability

C.

results from neurotoxic effects of the cholera toxin on the central nervous system

D.

is caused when the vibrios bind to the intestinal epithelium and physically or mechanically block

150.

the uptake of fluids by the gut epithelial cells

E.

*follows activation of adenylate cyclase by cholera toxin and the subsequent effect of cyclic

AMP on water and salt balances of the host cells

A person got cholera. What is the incubation period for cholerae?

A.

6 to 8 hours

B.

2 to 4 days

C.

1 to 2 weeks

D.

12 to 24 hours

E.

*48 to 72 hours

A stool sample is plated on standard Endo-agar plates. After overnight incubation some of the 151.

colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the bacteria that produced dark-pink colonies?

A.

Not likely to be ‘normal flora’.

B.

Non-motile.

C.

Produce capsules

D.

Gram-positive.

E.

*Ferment lactose.

152.

A test of the patient's serum shows reactivity with Helicobacter pylori antigens. Which of the following is true?

A.


B.


C.

All are true

D.


E.


153.

A urease-positive, spiral-shaped gram-negative rod is found in gastric washings from a 29-yearold stressed-out medical student with gastritis. Which of the following is most likely tobe this organism?

A.

Proteus mirabilis

B.

Providencia rettgeri

C.

Vibrio cholerae

D.


E.


154.

A young child develops bloody diarrhea, produced by Shigella infection. From which source was this infection most likely to have been contracted?

A.

Rare hamburger.

B.


C.

Dog or cat.

D.


155.

E.

*Another child.

A young man got a dysentery. Which Escherichia coli type is most like Shigella in its virulence plasmid and mode of infection:

A.

EHEC

B.

EPEC

C.

EAggEC

D.

ETEC

156.

E.

*EIEC

A young man got a dysentery. Which of the following is not true about Shigella?

A.

Causes bacillary dysentery

B.

Most strains are lactose nonfermenters

C.

Virulence is plasmid mediated

D.

The organism multiplies directly in the host cell

E.

*Serotyping is based on O and H antigens

157.

A young woman got a dysentery. Humans acquire shigellosis from:

A.

dogs

B.

cats

C.

swine

D.

chickens

E.

*humans

158.

159.

A young woman got cholera. The hallmark of therapy for severe cases of cholera is:

A.

antimicrobial therapy

B.

outpatient treatment

C.

serotherapy

D.

vaccination

E.

*replacement of electrolytes

A young woman got cholera. To determine to which species the infectious agent belongs, the microbiologist performs some tests on colonies cultured from stool samples. These tests include the following EXCEPT:

A.


B.

serotyping based on O antigens

C.


D.


E.


160.

Among the Sunday night patients at the Smithville emergency room were ten young adults suffering from severe diarrhea. All are true individuals would normally characterize themselves as being in good health. All reported eating at a local Dairy fair during the weekend. Of the following bacterial species the least likely to be responsible is

161.

A.

Campylobacter fetus

B.

Shigella flexneri

C.


D.

Yersina enterocolitica

E.

*Salmonella typhimurium

An engineer recently returned from visiting his family in India develops severe diarrhea. He in fact has cholera. His diarrhea is produced by a protein exotoxin secreted by Vibrio cholerae. How does this toxin act?

A.


B.


C.


D.


E.


162.

Both the E. coli LT toxin and the cholera toxin

A.

have an A+B subunit arrangement

B.

are identical in their primary structure

C.

are ADP-ribosylating toxins

D.

have an enzymatic mechanism of action

E.

*all answers are correct

163.

By which of the following methods Helicobacter pylori, a cause of peptic ulcers and gastric carcinoma, is diagnosed?

A.

Serology (serum) test

B.

Biopsy (invasive)

C.

Radioactive isotope C14 test

D.

All answers are correct

E.

*Bacteriological method

164.

During the procedure a biopsy of the stomach epithelium is obtained. Which observation would suggest Helicobacter pylori as the cause of illness?

A.

Biopsy shows infiltration of gastric epithelium by lymphocytes.

B.

pH of stomach fluid is equal to 1 (normal), rather than decreased.

C.

Ingested isotope-labeled nitrate is converted to nitrite in the stomach.

D.

Bacteria are found in stomach fluid, but not in contact with the gastric epithelium

E.

*Curved or spiral bacteria are seen in the biopsy after silver staining.

165.

From a 29-year-old stressed-out medical student with gastritis a urease-positive, spiral-shaped gram-negative rod is found in gastric washings. Which of the following is most likely to be this organism?

A.

Proteus mirabilis

B.


C.

Vibrio cholerae

D.


E.


166.

Gastroenteritis caused by Campylobacter jejuni is associated with consumption of contaminated water or foods which include the following EXCEPT:

A.

milk

B.

poultry

C.

chicken

D.

clams

E.

*hamburger

167.

Gastroscopy reveals that a patient with stomach pain has a large ulceration of his gastric mucosa.

During the procedure a biopsy of the stomach epithelium is obtained. Which observation would suggest

Helicobacter pylori as the cause of illness?

A.


B.


C.


D.


E.


168.

Healthy adult travelers visiting Peru are cautioned against eating uncooked vegetables and unpeeled fruits, and against drinking unbottled water. However, they are already resistant to cholera

169.

because of:

A.


B.


C.


D.


E.


If this patient had Shigellosis, the stool culture on MacConkey agar will grow:

A.


B.

pink colonies

C.

black colonies

D.


E.


170.

In a 30-year old patient with fever, nausea, vomiting and bloody diarrhea, all of the following bacteria should be considered in the diffrential diagnosis, except one:

A.

Salmonella

B.

Yersinia

C.

ETEC

D.

Shigella

E.

*Campylobacter

171.

Outbreaks of diarrhea caused by species of Shigella are common in day-care centers for children and other similar settings. What property of Shigella most enhances its spread between children?

A.

Frequent presence in the upper respiratory tracts of children who are not ill

B.

Ability to ferment lactose and grow in refrigerated milk.

C.

Possession of an envelope resistant to disinfectants.

172.

D.

Carriage by common classroom pets such as hamsters and gerbils

E.

*Resistance to stomach acid and low infectious dose.

Salmonella, Yersinia, Escherichia and Shigella are put together in Bergey's Manual because they

173.

are all

A.

gram-positive aerobic cocci

B.

fermentative

C.

none answers are correct

D.

pathogens

E.

*gram-negative facultatively anaerobic rods

The microbiologist is aware that the gastroenteritis outbreak is associated with the consumption

174.

of raw seafood at a local restaurant. She considers it may be due to a number of vibrios EXCEPT:

A.

V. parahaemolyticus

B.

V. alginolyticus

C.

V. vulnificus

D.

V. cholerae non 01

E.

*V. fluvialis

The severe diarrhea of cholera is produced by a protein exotoxin that acts on enterocytes. Which

175.

statement below best describes the effect of Cholera toxin?

A.


B.


C.


D.


E.


Which following measures does not prevent Vibrio parahaemolyticus infections?

A.

cook seafood for the appropriate time

B.

proper refrigeration

C.

vaccination

176.

D.

never return cooked seafood to the original container

E.

*consume alcohol along with raw seafood

Which microbe produce verotoxin?

A.

S. dysenterie serotype 2

178.

B.


C.

S.dysenterie serotype 8

D.

S.dysenterie serotype I0

E.

*Shigella dysenterie serotype I

177.

Which one of the following organisms is MOST likely to involve invasion of the intestinal mucosa?

A.


B.


C.


D.

Vibrio cholerae

E.

*Shigella sonnei

Young woman got cholera. Which of the following is the least accurate statement regarding

Vibrio cholerae?

A.

Cholera toxin is closely related to E. coli LT (heat labile toxin).

B.

Infected patients suffer from electrolyte deficiency and metabolic acidosis.

C.

Fimbrial adhesions produced by the organism facilitate adherence to the brush border of intestinal epithelial cells.

D.

Can grow on alkalaine media

E.

*Dark-field microscopic observation of stool from infected patients reveals large nonmotile rods.

179.

Your patient is a 30-year-old woman who was part of a tour group visiting a N. country. The day before leaving, several members of the group developed fever, abdominal cramps, and bloody diarrhea.

Of the following, which one is the LEAST likely organism to cause this infection?

A.


B.

Vibrio cholerae

C.


D.


180.

E.

*Shigella dysenteriae


181.

Which of the following bacterium is causative agent of dysenteriae?

A.

Klebsiella

B.

Proteus

C.

E. coli

D.

Vibrio

E.

*Shigella

The classic cause of epidemic cholera is Vibrio cholerae O1. The designation "O1" refers to the

182.

antigenic structure of an important component of the bacterial envelope. What is this component?

A.

Capsule.

B.

*Carbohydrate chains of LPS.

C.

Flagella

D.

Pili.

E.

Teichoic acid.


A.


B.


C.


D.


E.


183.


A.

Rare hamburger.

B.

Dog or cat.

C.


D.

*Another child.

E.


184.


A.

Frequent presence in the upper respiratory tracts of children who are not ill.

B.


C.


D.


185.

E.


Which phrase best describes typical infections by Campylobacter jejuni?

A.

Non-inflammatory enteritis

B.

*Inflammatory enteritis

C.

Systemic infection

D.

Urinary tract infection

E.

Meningitis

186.


A.


B.


C.


D.

Escherichia coli.

E.


187.




A.


B.


C.


D.


188.

E.


This bacterium, although usually not considered as normal flora, frequently colonizes the stomach and is thought to be the cause of gastric and duodenal ulcers.

A.

Lactobacillus acidophilus

B.


C.

Escherichia coli

D.

Vibrio cholerae

189.

E.


The large volume of fluid lost by diarrhea during infection with Vibrio cholerae

A.

is a consequence of fluid replacement during treatment of the disease and does not result directly

190.

191.

192.

from activity of the cholera toxin

B.


C.

is caused when the vibrios bind to the intestinal epithelium and physically or mechanically block the uptake of fluids by the gut epithelial cells

D.



E.


In the pathogenesis of Helicobacter pylori what is the colonization site in the host?

A.

nasal sinuses

B.

*stomach

C.

lower intestine

D.

throat

E.

respiratory tract

Which of the following statements about bacterial endotoxins is true?

A.

They usually act at a tissue site in the host that is removed from the site of bacterial growth.

B.

*They are nonantigenic.

C.

They typically have an enzymatic (specific) type of activity.

D.

They can be converted into toxoids.

E.

all are false

Bacterial endotoxins and exotoxins both share this property.

193.

194.

A.

They are proteins.

B.

They are structural components of the bacterial cell wall.

C.

They have an enzymatic type of activity.

D.

*They are toxic to animals.

E.

all are false

Both the cholera toxin and the E. coli LT toxin

A.


B.

*are identical in their primary structure

C.


D.


E.

all are true

The main effect of E. coli and Vibrio cholerae enterotoxin on host cells of the gastrointestinal

195.

tract that leads to the pathology of the diseases, is to

A.

inhibit protein synthesis

B.

*cause fluid and electrolyte imbalance

C.

cleave host cell membranes

D.

act as superantigens to trigger an overwhelming immunological reaction

E.

initiate a localized inflammatory response in the intestine

The common substrate of cholera toxin (ctx) and diphtheria toxin (dtx) is

A.

NAD

B.

cyclic AMP

C.

*ADP ribose

D.

ATP

196.

E.

elongation factor 2 (EF-2)

The portion of the bacterial lipopolysaccharide (LPS) that is responsible for the toxicity of the molecule is

A.

*lipid A

B.

lipoteichoic acid

C.

O polysaccharide

D.

Omp A

E.

N-acetylglucosamine (NAG)

197.

The portion of lipopolysaccharide (endotoxin) molecule that is responsible for a bacterium’s antigenic specificity, as well as the existence of multiple serotypes (serovars) among Gram-negative pathogens, is

A.

lipid A

B.

KDO

C.

*O polysaccharide

D.

R antigen

E.

H antigen

198.

A reason not to administer beta lactam antibiotics for a Gram-negative septicemia (blood-borne infection), unless there is no other alternative, is

A.


B.


C.


D.


E.


199.

Which of the following bacteria belong/s to the family Enterobacteriaceae?

A.

Shigella.

B.

Salmonella.

C.

Yersinia.

A.

D..Proteus

D.

*All are true

200.

Which of the following media is an enrichment medium for the isolation of Shigella?

A.

*Selenite F broth.

B.


C.


D.


201.

202.

E.

Endo medium

Which of the following bacteria is more resistant to adverse environmental conditions?

A.

Shigella dysenteriae.

B.

S. Flexneri.

C.

*S. boydii.

D.

S. sonnei.

E.

Salmonella typhy

Which of the following bacteria can grow in alkaline pH?

A.

Lactobacilli.

B.

*Vibrio cholerae.

C.

Salmonella.

D.

Shigella.

E.

Neisseria

203.

Which of the following bacteria is negative for fermentation of mannitol?

A.

*Shigella dysenteriae.

B.

S. Flexneri.

C.

S. boydii.

D.

S. sonnei.

E.

All are true.

204.

Which of the following tests can differentiate between classical and El Tor biotypes of Vibrio cholerae?

205.

A.

Sensitivity to polymyxin B.

B.

Agglutination of fowl RBCs.

C.

Sensitivity to Mukerjee's group IV phage.

D.

*All are true.

E.

Antigenic structure


A.

E. coli

B.

Klebsiella

C.

Proteus

D.

Vibrio

E.

*Shigella

Which of the following represents a major difference between Salmonella and Shigella 206.

infections?

A.

incubation period

B.

mode of transmission

C.

*place of location in intestine

D.

presence/absence of fever and diarrhea

E.

the portal of entry

207.

208.

The best treatment for cholera is

A.

antiserum injection

B.


C.

tetracycline

D.

toxoid

E.

vaccine

Water to be used for parenteral injection must sterilized to kill living microbes and then further

209.

purified to remove non-living bacterial components. Of those listed below, which is the most toxic?

A.

*Lipopolysaccharide.

B.

Polysaccharides of capsules.

C.

Plasma-membrane lipids.

D.

Proteins of the outer membrane.

E.

Nucleic acids

A stool sample is plated on standard Endo-agar plates. After overnight incubation some of the colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the bacteria that produced dark-pink colonies?

A.

Gram-positive.

B.

*Ferment lactose.

C.


D.

Non-motile.

210.

E.

Produce capsules



A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

211.

The severe diarrhea of cholera is produced by a protein exotoxin that acts on enterocytes. Which statement below best describes the effect of Cholera toxin?

A.


B.


C.


D.


E.


212.

213.


A.


B.


C.

Escherichia coli.

D.


E.



A.


B.


C.

heat stable

D.

heat resistent

E.


214.

Which of the following tests may be used to differentiate Salmonella typhi from Shigella species?

A.

glucose fermentation

B.

gas production from glucose

C.

*motility

215.

D.

citrate utilization

E.

color of colonies on Endo medium

Which of the following tests may be used to differentiate Salmonella paratyphi from Shigella

216.

species?

A.

Fermentation of glucose

B.

*gas production from glucose

C.

gram staining

D.

citrate utilization of Simmons’ citrate agar

E.

shape

Helicobacter pylori is a causetive of peptic ulcers and gastric carcinoma. Which of the following

217.

methods is used for diagnos?

A.


B.

Biopsy (invasive)

C.


D.

*All are true

E.

All are false

What is the cause of food poisoning?

A.

*Campylobacter jejuni

B.

Salmonella enteriditis

C.

Escherichia coli

D.


218.

E.

*All are true

What is the incubation period for Shigella dysenteriae?

A.

6 to 8 hours

B.

24 to 48 hours

C.

*2 to 4 days

D.

1 to 2 weeks

219.

E.

All are false

The pathogenesis of which one of the following organisms is MOST likely to involve invasion of the intestinal mucosa?

A.

Vibrio cholerae

B.

*Shigella sonnei

C.


220.

D.


E.

All are true

Each of the following statements concerning en-terotoxins is correct EXCEPT:

A.

*Enterotoxins typically cause bloody diarrhea with leukocytes in the stool

B.

Staphylococcus aureus produces an enterotoxin that causes vomiting and diarrhea

C.

Vibrio cholerae causes cholera by producing an enterotoxin that activates adenylate cyclase

D.

Escherichia coli enterotoxin mediates ADP-ribosylation of a G protein

E.

All are true

221.

are all

Escherichia, Salmonella, Yersinia, and Shigella are put together in Bergey's Manual because they

A.

pathogens

B.


C.


D.

fermentative

222.

E.

all are false

A 6 years old child, who goes to primary school, has a whooping cough. What preparation is used for the prophylaxis of whooping cough for children?

A.

TABTte

B.

ADT

C.

AD

D.

Human immunoglobulin

223.

E.

*Pertussis-diphtheria-tetanus vaccine

7 years old child is in the infectious department with a diphtheria of pharynx. Material, which was taken from greyish film on tonsils, was inoculated Klauberg medium. In 2 days there were typical

224.

colonies of С. diphtheriae. What next stage of examination must be done?

A.

To examine biochemical properties of microbes

B.

To examine toxigenic properties of microbes

C.

To examine the production of urease, nitrate reductase

D.

To stain microbes by Ziehl-Neelsen technique

E.

*To examine bacterial toxigenicity and examine cystinase production

A 2 year old child presented with a membrane in the mouth. Within 24 hrs a culture report is

225.

needed. The preferred medium is ____

A.

Blood agar

B.

Lowenstein-Jensen medium

C.

Tellurite agar

D.

Sugar agar

E.

*Loeffler medium

A 55-year-old man has a two month history of fever and weight loss. He has recently begun to cough up yellow-green sputum, sometimes with blood in it. X-rays show evidence of lung inflammation and damage. He is given a PPD skin test. Which statement below about the results of PPD testing is most accurate?

A.

A positive PPD test indicates active tuberculosis.

B.

A PPD test may yield a false-positive result in a person with advanced disease [who may be anergic].

C.

A PPD test can cause a person (previously un-exposed to Mycobacterium tuberculosis) to covert to PPD-positive status, and so can be performed only once on a patient.

D.

A positive PPD test indicates high level of immunity.

E.

*A PPD test may produce a false-negative (or weakly-positive) result if the patient has impaired cell-mediated immunity.

A 6 years old child has paroxysmal cough during 3 days. Whooping cough was diagnosed. What 226.

tested material for examination is it needed to take first to confirm a diagnosis?

A.

Patient’s blood

B.

*Smear from the posterior wall of the throat

C.

Pus

D.

Patient’s serum

E.

Vomiting masses

227.

A baby was born in a maternity hospital. What vaccine is prescribed him before discharge from a hospital?

A.

Vaccine against whooping cough, diphtheria, and tetanus

B.

Attenuated poliomyelitis vaccine

C.

EV 76 vaccine

D.

Attenuated influenza vaccine

E.

*BCG

228.

A child has a common cold which progresses to severe pharyngitis. Pharyngeal exudate forms a tough membrane difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which

229.

organism is most likely to have caused this infection?

A.

Actinomyces israelii.

B.

Bordetella pertussis.

C.

Candida albicans.

D.

Mycobacterium avium/intracellulare.

E.

*Corynebacterium diphtheriae.

A child has severe pharyngitis. Pharyngeal exudate forms a tough 'membrane', difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which organism below is most likely to have caused this infection?

A.


B.


C.


D.

Mycobacterium avium/intracellulare

230.

E.


A girl, 7 years of old was admitted to the hospital with the high temperature, throat pain general weakness. A doctor suspected diphtheria and took material from pharynx for isolation of pure culture of

231.

Corynebacterium. What test can confirm the diagnosis of diphtheria?

A.

Examination of volutin granules

B.

Examination of cystinase production

C.

Examination of hemolytic properties

D.

Susceptibility to phages

E.

*Examination of bacterial toxigenicity

A growth of tuberculosis bacteria on nutrient media takes a place in 3 weeks, sometimes in 2-3 months. But express technique for there cultivation, Prices and Shkolnikov’s methods may be used. In what time is it possible to get growth of tuberculosis microcultures?

A.

3-4 days

B.

20-30 days

C.

over 40 days

D.

over 50 days

E.

*7-10 days

232.

A man, 40 years old has chronic kidneys infection. During examination of urine acids fast rodshaped microbes were revealed. They did not grow on simple nutrient media, but on Loewenstain-

Jensen medium in a few weeks they formed dry yellowish colonies. What group of microorganisms could cause his disease?

A.

Chlamidia

B.

Mycoplasma

C.

Trichomonas

D.

Gardnerella

E.

*Mycobacteria

A microbiologist put a few drops of 1% Ziehls phenol fuchsine on a paper which covers a smear 233.

from patients sputum, heat it until steam rose. He repeated this procedure three times. Then took off a paper, put a smear in 5 % sulphuric acid, washed with water and stained by methylene blue. What microbes can be examined by this technique?

A.

S. aureus

B.

S. pneumoniae

C.

S. viridans

D.

K. pneumoniae

E.

*M. tuberculosis

234.

A mother with a 5 years old girl, who has a cough and flu-like state during 2 weeks, visited the doctor. Last time a cough increased, paroxysmal cough appeared. A doctor diagnosed whooping-cough.

What factors do determine virulence of Bordetella pertussis?

A.

Exotoxin

B.

Pili

C.

Hyaluronidaze

D.

Histamin-sensitizing factor

E.

*Thermolabile toxin

235.

A patient has cough with discharges of sputum. During microscopic examination after staining this smear by Ziehl-Neelsens technique dark blue cocci, which form irregular clasters and rod-shaped red bacteria were revealed. What microorganisms may be a reason of disease?

A.

Actinomyces bovis

B.


C.

E.coli

D.

Corynebacterium diphtheriae

236.

E.

*Mycobacterium tuberculosis

A sick child was tested by Mantouxs test. In 24 hours there were tumidity, hyperemia and painfulness in the place of allergen injection. What basic mechanisms do provide this reaction of a

237.

body?

A.

Granulocytes, T- lymphocytes, and Ig G.

B.

Plasma cells, T-cell, and lymphokines

C.

B-lymphocytes, IgM

D.

Macrophages, B-lymphocytes, and monocytes

E.

*Mononuclear cells, T-cell, and lymphokines

According to epidemiological indication in preschool it is necessary to make vaccination against

238.

a whooping cough. What preparation may be used?

A.

live attenuated pertussis vaccine

B.

BCG vaccine

C.

Human immunoglobulin

D.

Killed pertussis vaccine

E.

*Pertussis-diphtheria-tetanus vaccine

After making Mantouxs test in a child of 4 years old in 72 hours a reddening of the skin in the

239.

place of injection of tuberculin is not observed. What does this result testify?

A.

A child has tuberculosis

B.

A child is vaccinated against tuberculosis

C.

A child is a carrier of tuberculosis bacteria

D.

A child is infected by tuberculosis bacteria

E.

*A child is not vaccinated against tuberculosis

After staining of patient’s sputum by Ziehl-Neelsen technique red rod-shaped bacteria were revealed. The first signs of bacterial growth appeared in 17 days. What bacteria may be there in the smear?

A.

Yersinia pseudotuberculosis.

B.

Histoplasma dubrosii

C.

KlРµbsiella rhinoscleromanis

D.

Coxiella burnetii

240.

E.


After vaccination of babies by BCG vaccine immunity to tuberculosis lasts until there are living bacteria of vaccine strain in an organism. What is correct name of such type of immunity?

A.

Type specific

B.

Humoral

C.

Species inherited

D.

Natural

241.

E.

*Non-sterile

Bacteriological laboratory urine from a patient with an initial diagnosis of kidneys tuberculosis must be investigated in bacteriological laboratory. What method of diagnosis is it better to utilize?

A.

Bacteriological

B.

Bacterioscopy

C.

Serological

D.

Allergic

242.

E.

*Biological

Bordets nutrient medium is utilized for isolation of causative agent of whooping cough from clinical material. What component is not necessarily included in its composition?

A.

Glycerol

B.

Potato starch

C.

Blood

D.

*РҐ-factor

243.

E.

all are true

9 years old has diphtheria of pharynx. What was the way of diphtheria transmission?

A.

Fecal-oral

B.

*Air born

C.

Sexual

D.

Contact

244.

all?

E.

No way

Diphtheria was diagnosed in 4 years old child. What preparation is it necessary to inject first of

A.

TABTe.

B.

Diphtherial toxoid

C.


D.

Vaccine against diphtheria and tetanus

245.

E.

*Diphtherial antiserum.

During examination of bacterial carriers in the kindergarten one nurse showed the presence of

Corynebacterium in her throat. The production of toxin by Corynebacterium diphtheriae was checked.

246.

It did not produce exotoxin. What test was used for examination of toxigenicity?

A.

Agglutination test

B.

Ring precipitation test

C.

*Precipitation test in gel

D.

Complement fixation test

E.

Immunofluorescence test

During examination of patient’s sputum, which was inoculated by Prices technique, rod-shaped

247.

bacteria appear as plaits. What substance from tuberculosis bacilli does form such pictures?

A.

Tuberculin.

B.

*Cord-factor

C.

Phtionic acid (phosphatide).

D.

Fatty acids.

E.

PPD.

During examination of patient’s sputum, which was stained by Ziehl-Neelsen, method microbiologist saw red thin, long rods appeared as plaits. What method of cultivation was utilized?

A.

Loefllers

B.

Drygalskys

C.

*Prices

D.

Mantoux

E.

Kalmett-Guerin

248.

During the examination child 6 years of old a doctor noticed greyish film on the surface of tonsils. During the attempt of it’s deleting moderate bleeding appeared. During bacterioscopy after

Neissers staining: rods display club-shaped swellings, volutin granules. What symptoms will appear in a

249.

child in the nearest days, if specific treatment will not be prescribed?

A.

Oedema of lungs

B.

*Toxic lesion of cardiac muscle and kidneys

C.

Paroxysmal cough

D.

Papular rashes on a skin

E.

Disorders of digestion

Every year pediatricians use Mantouxs allergic for checking of the children and teenagers. What

250.

is the aim of this test?

A.

Treatment of tuberculosis

B.

Prophylaxis of tuberculosis

C.

Vaccination

D.

*A selection of children for revaccination by BCG vaccine

E.

No correct answer

Five days old boy has planned immunization with BCG vaccine. In 7 years doctor prescribed repeated immunization with the same vaccine. What examination was the basis of such doctor’s decision?

A.

Examination of antimycobacterial antibodies

B.

*Skin allergic test

C.

Medical and genetic examination

D.

Bacterioscopy of childs sputum

E.

X-ray examination of the lungs

251.

Five years old child was admitted to the hospital with a diagnosis of diphtheria of pharynx.

Material, which was taken from greyish film on tonsils, was inoculated Klaubergs medium. What are there properties of Corynebacterium colonies on this medium?

A.

Colonies are convex, with even edges, colorless

B.

Colonies are rounded, concave in a center, white

C.

Colonies are protuberant, viscid, remind a shagreen skin, grey

D.

Colonies are rosette-like, a surface is knobby, yellow

252.

E.

*Colonies are grey, round, rosette-like

For a patient with suspicion of diphtheria microbiologist found rod-shaped bacteria with granules of volutin? What method might be used for staining?

A.

Ziehl-Neelsen

B.

Gram

C.

Burry-Gins

D.

Anjesky

E.

*Neisser

253.

For diagnosis of tuberculosis infection among schoolboys it is necessary to make allergic intracutaneous Mantouxs test. What preparation may be used for the test?

A.

*Tuberculin

B.

BCG vaccine.

C.

STI vaccine.

D.

Anthraxin.

E.

Brucellin

254.

For examination of Corynebacterium diphtheriae toxigenicity these microbes were inoculated on the agar and paper strip impregnated with antitoxic serum was put on the surface of gel. After incubation precipitation lines between the bacterial plaques and paper strip appeared in agar. What serologic test was used?

A.


B.

Kumbss test

C.

Agglutinations test

D.


E.

Opsonization test

255.

For rapid cultivation of Mycobacterium tuberculosis Pryces and Shkolnikovas methods are used.

What factor of virulence may be revealed by this technique?

A.

Lecithinase

B.

Capsule formation

C.

*Cord-factor

D.

Neuraminidase

256.

E.

DNA-ase

From nasal part of pharynx of child of 4 years old rod-shaped microorganisms were isolated.

According to their morphological and biochemical properties they were identical to Corynebacterium

257.

diphtheriae, but did not produce exotoxin. By what way can this microorganism become toxigenic?

A.

Chromosomal mutation.

B.

Cultivation on a tellurate medium

C.

Passages through the organism of susceptible animals

D.

Cultivation in a presence of antitoxic serum.

E.

*Phage conversion

In 1874 G. Hansen described the causative agent of serious human infectious chronic disease, which has very long incubation. Specific infiltrates вЂ“ lepromas are formed in patients. What family does the causative agent of disease belong to?

A.

Corynebacteriaceae

B.

Enterobacteriaceae

C.

Actinomycetaceae

D.

*Mycobacteriaceae

E.

Rickettsiaceae

258.

In 6 years old child with paroxysmal cough mucous from oropharynx was taken. This material was inoculated on glycerin-potatoes agar. In 72 hrs of cultivation at 37 C there were small greyish convex, and glistening, resembling globules of mercury appeared. What causative agent did cause this

259.

disease?

A.


B.


C.


D.

*Bordetella pertussis

E.

Mycobacteria tuberculosis

In 8 years old child active tuberculosis process was suspected. Diagnostic Mantouxs reaction was made. In 30 minutes after the injection there was an insignificant erubescence in the place of injection. In 24 hours the phenomenon of dermahemia disappeared. What does the result of reaction testify to?

A.

Postvaccinal immunity

B.

Active tubercular process.

C.

*A reaction is negative

D.

A tuberculosis process is occult

E.

A reaction is positive

260.

In a 6 years old child active tuberculosis process was suspected. Diagnostic Mantouxs reaction was made. What immunobiological preparation was used?

A.

Pertussis-diphtheria-tetanus vaccine.

B.

BCG vaccine.

C.

*Tuberculin.

D.

Tulyarin.

E.

No correct answer

261.

In a child with the suspicion of diphtheria a swab from the mucus membrane of pharynx was taken. After staining by Loeffers method dark-blue granules of volutin were revealed in bacteria. What value does their examination have?

A.

*Diagnostic

B.

Treatment

C.

Prophylactic

D.

None of them

E.

All answer are correct

262.

In a maternity hospital it follows newborn to execute an inoculation against tuberculosis. What preparation must be here utilized?

A.

Vaccine of EV.

B.

Vaccine of STI

C.

*Vaccine of BCZH

D.

Vaccine of AKDP

263.

E.

Tuberculin

In a smear from a patients tonsils with suspicion of diphtheria blue rod-shaped bacteria display terminal club-shaped swellings, which stained more intensely at their end were revealed. What method

264.

of staining was utilized?

A.

Gram

B.

Burry

C.

Giemsa

D.

*Loeffler

E.

Neisser

In an infectious department there is a girl, 10 years of old with a diagnosis diphtheria of pharynxвЂќ. Toxigenic strain of Corynebacterium diphtheriae was isolated. How can you examine the strain toxigenicity?

A.

By agglutination test

B.

By complement fixation test

C.

*By precipitation test in a gel

D.

By indirect haemagglutination test

E.

By flocculation test

265.

In kindergarten whooping cough was diagnosed in 3 children. In what clinical periods of whooping cough they may be most contagious?

A.

Latent period

B.

Paroxysmal period

C.

*Catarrhal period

D.

Regenerative period

266.

E.

Period of reconvalescence

In tonsils smear yellow brown rod-shaped bacteria with dark blue granules of volutin were revealed. What method of staining was utilized?

A.

Gram

B.

Anjesky

C.

Loeffler

D.

*Neisser

267.

E.

Ziehl-Neelsen

Leprosy was suspected in a patient. What skin-allergic test can confirm this diagnosis?

A.

Dick

B.

Moloni

C.

*Mitsuda

D.

Kumbs

E.

Shick

268.

Mantouxs allergic test was made in young man of 16. Test was negative. What is the most rational tactics of doctor?

A.

*To make vaccination by BCG vaccine

B.

To repeat a test in month

C.

To make serologic diagnosis of tuberculosis

D.

Quickly to isolate this young man from a collective

E.

To make rapid diagnosis of tuberculosis by Prices method

269.

Mantouxs test is a specific diagnostic test. The results of allergic test we estimate in 72 hours.

What is positive result?

A.

*diameter of papule 5 mm and more

B.

diameter of hyperemia 5-10 mm

C.

diameter of papule 3-7 mm

D.


E.


270.

On the tonsils of boy of 12 which got the planned vaccination by pertussis-diphtheria-tetanus vaccine the microorganisms identical to Corynebacterium diphtheriae according to their morphological and biochemical signs were isolated. The precipitation test in gel with an antitoxic serum gave positive result. What form of infectious process can this causative agent cause?

A.

*Asymptomic bacterial carriage

B.

Ligh non toxic form of disease

C.

Toxic complicated form of disease

D.

Chronic disease with lesion of internal organs

E.

Persisting infection

271.

Pathogenesis of considerable part of infectious diseases is related to the action of bacterial protein toxins, which have selective action on different organs and tissues of the body. Show, what toxins is the strongest cellular poison and blocks the synthesis of protein:

A.

Staphylococcal toxin

B.

*Diphtherial histotoxin

C.

Tetanospasmin

D.

Botulinum neurotoxin

272.

E.

Cholerae enterotoxin

Patient has initial diagnosis of lung tuberculosis. What nutrient medium may be used for isolation of mycobacteria:

A.

glycerin-potatoes agar

B.

*Loewenstein-Jensen medium

C.

salt-salt agar

D.

blood agar

273.

E.

Ploskirev medium

Patients sputum was sent to a laboratory. What method of staining does it follow to utilize for the examination of causative agents of tuberculosis?

A.

Gram

B.

Giemza-Romanovsky

C.

Gins-Burry

D.

*Ziehl-Neelsen

E.

Neissers

274.

Seven years old child has fever and paroxysmal cough. Similar symptoms were observed in a senior brother month ago. There may be whooping cough. What method is it possible to use for retrospective diagnosis of this disease?

A.

*Serological

B.

Bacteriological

C.

Biological

D.

Morphological

E.

Allergic

275.

The child has diagnosis of diphtheria of pharynx. The clinical diagnosis is confirmed by bacteriologic examinations: toxigenic Corynebacterium diphtheria was isolated. What preparations do apply for specific treatment?

A.

Antibiotics

B.

Sulfonamides

C.

Toxoid

D.

*Antitoxic serum

276.

E.

NO correct answer

The presence of lipid cord factor in a cell wall of tuberculosis bacilli leads to that this microorganism is absorbed by phagocytes, but do not kill. What term does determine this property of

277.

microorganism most exactly?

A.

Pathogenicity

B.

Invasiveness

C.

*Aggressiveness

D.

Colonisational resistance

E.

Toxigenicity

The toxigenicity of causative agents of diphtheriae is directly associated with determinants of toxigenicity (tox+-genes). Where do these genes localize?

278.

A.

*In DNA of temperate phages

B.

In Hly plasmids

C.

In Ent plasmids

D.

In DNA of causative agents

E.

In transposones

There is 7 years old child with a diagnosis of diphtheria of pharynx. What tested material must be taken for isolation of causative agent and confirmation of diagnosis?

A.

Patients blood

B.

Patients serum

C.

*Swab from the pharynx

D.

Sputum

E.

Pus

279.

There is a bacteriological method for laboratory diagnosis of diphtheria. For cultivation of РЎ. diphtheriae it is necessary to know the some bacterial properties. According to the type of respiration is

РЎ. diphtheriae:

A.

Obligate aerobe

B.

*Facultative anaerobe

C.

Obligate anaerobe

D.

Microaerophilic bacterium

280.

E.

Capneic bacterium

There is a bacteriological method for laboratory diagnosis of diphtheria. For cultivation of РЎ. diphtheriae it is necessary to know the some bacterial properties. What nutrient media it is necessary to

281.

use for cultivation of Corynebacterium diphtheriae?

A.

Serum agar

B.

*blood agar, blood tellurite agar

C.

sugar MPB, sugar MPA

D.

yolk-salt agar

E.

Endo, Ploskirev

When doctor examined a child of 6 years old he revealed the greyish film on the tonsils. He took this film, stained by Neisser's technique. What morphological feature was most substantial for confirmation that these microbes are Corynebacteria?

A.

Localization of microbes in macrophages

B.

*The presence of volutin granules at the ends of microbes

C.

Presence of spores, their diameter is more then diameter of the cell

D.

Presence of flagella

E.

Presence of capsule

282.

Which line below correctly pairs a bacterial group or species with an antibiotic that currently inhibits enough of its members to be used against it, before results of sensitivity testing are received?

Many Bacteria are sensitive to

A.

Enterobacteriaceae, Penicillin G

B.

Staphylococcus aureus, Penicillin G

C.

*Mycobacterium tuberculosis, Isoniazid

D.

Obligate anaerobes, Aminoglycosides

283.

E.

Obligate aerobes, Metronidazole

Which of the following is spread by close person-to-person contact through the inhalation of infectious aerosols and infects a third of the worlds population according to the World Health

284.

Organization (WHO)?

A.

M. leprae

B.

M. avium-intracellulare

C.

*M. tuberculosis

D.

E.coli

E.

S. paratyphi A

Which of the following is spread by person-to-person contact, has fallen in prevalence by almost

90% since 1985, and is endemic in armadillos?

A.

*M. leprae

B.

M. avium-intracellulare

C.

M. tuberculosis

D.

M. paratuberculosis

E.

M. scrofulaceum

285.

Which of the following primarily affects immunocompromised patients, has not shown personto-person transmission, is acquired through ingestion of contaminated water or food, is seen most commonly in countries where tuberculosis is less common?

A.

M. leprae

B.

*M. avium-intracellulare

C.

M. Tuberculosis

D.

M. paratuberculosis

286.

E.

M. scrofulaceum

Whooping cough is acute mainly child's infectious disease which is characterized by catarrhal inflammation of respiratory tracts and attacks of paroxysmal cough. Virulence of Bordetella pertussis is

287.

determined by all the factors, EXCEPT:

A.

Pertussis thermolabile exotoxin

B.

Pili

C.


D.

Endotoxin

E.

*Capsule formation

A patient is diagnosed with Clostridium difficile colitis. Which item would represent a known risk factor for such infections?

A.

*Been treated with antibiotics.

B.

Consumed unpurified water.

C.

Visited the southwestern United States.

D.

Eaten undercooked fried rice.

E.

Been in contact with livestock

288.

289.

ANSWER:A

A 22-year-old develops an abscess in his peritoneum following rupture of his appendix. Gram stain of exudate from his foul-smelling abscess reveals numerous polymorphonuclear leukocytes, Grampositive cocci, Gram-positive rods, and Gram-negative rods. Aerobic culture of the exudate at 37oC on blood and MacConkey agar yields only Enterococci. Which of the bacteria below is most likely to be the Gram-negative rods seen in the stained smear?

A.


B.

Proteus mirabilis.

C.

Klebsiella pneumoniae.

D.

Prevotella melaninogenica.

E.

*Bacteroides fragilis.

290.

A 61-year-old diabetic man is admitted to the hospital for severe pain in his right leg; the diagnosis is obstruction of the femoral artery. The affected area of the leg is painful, red, and swollen.

During the next 12 hours the swelling increases markedly, the skin of the leg becomes discolored, and fluid-filled blisters appear on the skin. Gram stain of fluid aspirated from a blister reveals large Grampositive rods. Which organism below is most likely to have caused this infection?

A.

Clostridium botulinum.

B.

Clostridium difficile.

C.

*Clostridium perfringens.

D.

Clostridium tetani.

E.

Listeria monocytogenes.

291.

The young man was injuring in car accident. The affected area of the leg is painful, red, and swollen. During the next 12 hours the swelling increases markedly, the skin of the leg becomes discolored, and fluid-filled blisters appear on the skin. Gram stain of fluid aspirated from a blister

292.

reveals large Gram-positive rods. Which organism below is most likely to have caused this infection?

A.


B.


C.


D.

Clostridium tetani.

E.


Bacteroides fragilis is isolated from an abdominal abscess. Which phrase below best describes infections like this one?

293.

294.

295.

296.

297.

298.

299.

300.

301.

A.

*Other species of bacteria are also often present.

B.

Initiated by ingestion of spores.

C.

Can be successfully treated with aminoglycosides alone.

D.

Contracted by the respiratory route.

E.

Sexually-transmitted.

Both the botulinum toxin and the tetanus toxin

A.

A. are produced by Bacillus anthracis

B.

act in the central nervous system

C.

*act in the peripheral nervous system

D.

are Zn++ dependent protease enzymes

E.

two of the above

The clostridial invasin that dissolves the framework of muscle is

A.

botulinum toxin

B.

tetanus toxin

C.

*hyaluronic acid

D.

neuraminidase

E.

collagenase

Both the botulinum toxin and the tetanus toxin are

A.

superantigens

B.

enterotoxins

C.

adenylate cyclase enzymes

D.

*protease enzymes

E.

all are false

The common mode of action of the tetanus and botulinum toxins is to

A.

*block the release of neurotransmitters across a neural synapse

B.

up-regulate the production of cAMP in affected cells

C.

cause the ADP ribosylation of neuron gangliosides

D.

block protein synthesis in target cells

E.

cleave neuraminic acid in the intercellular space

Passive immunity to tetanus in a susceptible host would be accomplished by

A.

recovery from the disease tetanus

B.

injection with tetanus toxin

C.

injection with tetanus toxoid (as in the DPT vaccine)

D.

*administration of donor’s antitetanus immunoglobulin

E.

two of the above

Active artificial immunity to tetanus is accomplished by

A.

tetanus antitoxin (antiserum) administration

B.

*vaccination with tetanus toxoid

C.

recovery from the disease tetanus

D.

all are true

E.

all are false

Antitoxic therapy is useful in:

A.

gas gangrene.

B.

diphtheria.

C.

tetanus

D.

* all are true

E.

all are false

Typical drumstick appearance of bacilli is observed in:

A.

Clostridium perfringens.

B.

C. tetani.

C.

С. botulinum.

D.

*C. histolyticum.

E.

C. difficilae

Bacterial genus/genera of medical importance which produce Endopores is/are:

A.

Staphylococcus

B.

all are true

C.

*Clostridium.

302.

303.

304.

305.

306.

307.

308.

309.

310.

311.

D.

Bacteroides

E.

all are false

Which of the following exotoxins is most toxic?

A.

*Botulinum toxin.

B.

Tetanus toxin.

C.

Diphtheria toxin.

D.

Cholera toxin.

E.

Shigella toxin

Infective-toxic type of food poisoning is caused by:

A.


B.

Salmonella Enteritidis.

C.


D.

Salmonella Dublin.

E.

Yeasts

The causative agent/s of gas gangrene is/are:

A.


B.

C. novyi.

C.

С. septicum.

D.

C. histolyticum

E.

*all are true.

Which of the following properties is/are characteristic of tetanospasmin?

A.

It is a heat-labile protein.

B.

It is a neurotoxin.

C.

It can be toxoided.

D.

It is exotoxin

E.

* all are true

Which of the following exotoxins resembles strychnine in its effect?

A.

Botulinum toxin.

B.

*Tetanus toxin.

C.

Diphtheria toxin.

D.

All are false

E.

All are true

Each of the following is a typical property of obligate anaerobes EXCEPT:

A.

*They generate energy by using the cytochrorne svstem

B.

They grow best in the absence of air

C.

They lack superoxide dismutase

D.

They lack catalase

E.

They grow in Kitt-Tarozi medium

What is the usual habitat of Endopore-forming bacteria that are agents of disease?

A.

the intestine of animals

B.

*soil

C.

water

D.

foods

E.

dust

Most Bacillus species are

A.

true pathogens

B.

opportunistic pathogens

C.

*nonpathogens

D.

commensals

E.

saprophyticus

Many clostridial diseases require a/an conditions for their development.

A.

*anaerobic

B.

aerobic

C.

living tissue

D.

low-pH

E.

alkaline pH

Clostridium perfringens causes

312.

313.

314.

A.

*myonecrosis, food poisoning

B.

enterocolitis, haemorrhagic syndrom

C.

antibiotic-induced colitis

D.

All are true

E.

No correct answer

The action of tetanus exotoxin is on the

A.

neuromuscular junction

B.

sensory neurons

C.

nucleus of hypocamp

D.

cerebral cortex

E.

*spinal interneurons

Which infectious agent cause pseudomembranous collitis?

A.

Mycobacterium tuberculosis

B.


C.

Mycobacterium leprae

D.


E.

*Shigella sonnei

Which infectious agents cause food poising?

A.

Bacillus anthracis

B.

Clostridium tetani

C.

*Clostridium perfringens

D.


E.

all of these

315.

A child at-risk for Tetanus is treated with Tetanus immune globulin (human). What is a major advantage of this method for immunization over the use of Tetanus toxoid?

A.

Poses a reduced risk of serum sickness.

B.

Provides longer-lasting immunity.

C.

*Provides protection more rapidly.

D.

Results in higher antibody titer.

316.

E.

Also provides secretory IgA for mucosal immunity.

A child under treatment for leukemia is treated with Tetanus immune globulin (human). Which phrase best describes the immunity that is produced?

A.

Innate and specific.

B.

Innate and humoral.

C.

Innate and cell-mediated.

D.

*Acquired and humoral.

317.

E.

Acquired and cell-mediated.

A 20-year-old student has a deep laceration. He received the standard four-doses of Diphtheria-

Pertussis-Tetanus immunizations in infancy, and a booster at age 5, but has had no anti-Tetanus

318.

immunization since. Which of the following would it be most appropriate to administer?

A.

Tetanus toxoid.

B.

Tetanus anti-toxin (equine).

C.

Tetanus immune globulin (human).

D.

*Both Tetanus toxoid and Tetanus immune globulin (human).

E.

Both Tetanus toxoid Tetanus anti-toxin (equine).

A ten-year-old girl has dirty, crushing, wounds, received when she fell from a motorcycle. She

319.

has never been immunized against Tetanus. Which of the following should you administer?

A.

Tetanus immune globulin (human) Tetanus toxoid

B.

Tetanus anti-toxin (equine) Tetanus toxoid

C.

Tetanus toxoid Tetanus immune globulin (human)

D.

Tetanus toxoid plus Tetanus immune globulin (human),

E.

*Tetanus toxoid plus Tetanus immune globulin (human

A patient has rapidly spreading soft-tissue infection with gas in infected tissue. Fluid from a blister contains many large Gram-positive rods which grow on sheep blood agar anaerobically but not aerobically. Which pathogen is most consistent with these findings?

A.

Bacillus anthracis.

B.

Bacillus cereus.

C.


D.


320.

E.


The spastic paralysis of Tetanus is the effect of a protein exotoxin. Which phrase below best describes the process directly inhibited by Tetanus toxin?

A.

Synthesis of neurotransmitter.

B.

Transport of neurotransmitter into vesicles.

C.

Calcium influx required for neurotransmitter release.

D.

*Docking and fusion of neurotransmitter vesicles with the synaptic membrane.

321.

E.

Binding of neurotransmitter molecules to their receptors

An infant is brought to the emergency room, cyanotic and with poor muscle tone. Which condition is most likely given these findings?

A.

Antibiotic-associated colitis.

B.

Diphtheria.

C.

Anthrax.

D.

*Botulism.

322.

E.

Tetanus.

A patient has an abscess from which Bacterioides fragilis is isolated. Which condition is most likely to have facilitated infection by this organism?

A.

Treatment with trimethoprim/sulfa.

B.

*Tissue ischemia.

C.

Presence of neutrophils.

D.

Antibiotic treatment for another bacterial infection.

E.

Colonization of the large intestine with spores of this organism.

A.

A 50-year-old woman was treated for cystitis [caused by E. coli] with an oral broad-spectrum antibiotic.

Three weeks later she developed abdominal pain and diarrhea. A stained smear of stool contained many neutrophils. Cultures for bacterial pathogens were negative. A serological test of stool for Clostridium difficile toxin was positive. Which of the following is most likely to have been the immediately

323.

324.

predisposing cause of this patient’s C.difficile infection?

A.

Colonization of her large intestine by antibiotic-resistant E. coli.

B.

*Alteration of her intestinal flora by antibiotic treatment.

C.

An allergic response to her antibiotic treatment.

D.

Acquisition of an antibiotic-resistance plasmid (R-Factor) by C. difficile.

E.

All are true

Which of the following members of the Clostridium family causes pseudomembranous colitis?

A.

Clostridium tetan

B.

*Clostridium difficile

C.


D.


E.


Which of the following methods is used to help clear an anaerobic infection?

A.

Removal of dead tissue

B.

Drainage of infected area

C.

Oxidizing agents/hyperbaric chambers

D.

*All are true

E.

None of answers

325.

326.

What causes gas gangrene?

A.


B.

Leptospira interrogans

C.


D.

Escherichia coli

E.

Clostridium tetan

Each of the following organisms is an important cause of urinary tract infections EXCEPT:

A.

Escherichia coli

B.

Proteus mirabilis

C.


D.

*Bacteroides fragilis

327.

E.

All are true

The MOST important protective function of the antibody stimulated by tetanus immunization is

A.

To opsonize the pathogen (Clostridium tetani)

B.

To prevent growth of the pathogen

C.

To prevent adherence of the pathogen

D.

*To neutralize the toxin of the pathogen

328.

E.

All are true

Your patient is a 70-year-old man who under went bowel surgery for colon cancer 3 days ago.

He now has a fever and abdominal pain. You are concerned that he may have peritonitis. Which one of

329.

the following pairs of organisms is MOST likely to be the cause?

A.

*Bacteroides fragilis and Klebsiella pneumoniae

B.

Bordetella pertussis and Salmonella enteritidis

C.

Actinomyces israelii and Campylobacter jejuni

D.

Clostridium botulinum and Shigella dysente-riae

E.

All are true

Each of the following statements concerning Bacteroides fragilis is correct EXCEPT:

A.

B. fragilis is a gram-negative rod that is part of the normal flora of the colon

B.

*fragilis forms Endopores, which allow it to survive in the soil

C.

The capsule of B. fragilis is an important virulence factor

D.

B. fragilis infections are characterized by foul-smelling pus

E.

All are true

330.

Five days ago a 65-year-old woman with a lower urinary tract infection began taking ampicillin.

She now has a fever and severe diarrhea. Of the organisms listed, which one is MOST likely to be the cause of the diarrhea?

A.


B.

Bacteroides fragilis

C.

Proteus mirabilis

D.

Bordetella pertussis

E.

All are true

331.

Each of the following statements concerning exotoxins is correct EXCEPT:

A.

Some strains of Escherichia coli produce an enterotoxin that causes diarrhea

B.

Cholera toxin acts by stimulating adenylate cyclase

C.

Diphtheria is caused by an exotoxin that inhibits protein synthesis by inactivating an elongation

332.

333.

factor

D.

*Botulism is caused by a toxin that hydrolyzes lecithin (ledthinase), thereby destroying nerve cells

E.

All are true

Each of the following statements concerning Clostridium perfringens is correct EXCEPT:

A.

It causes gas gangrene

B.

It causes food poisoning

C.

It produces an exotoxin that degrades lecithin and causes necrosis and hemolysis

D.

*It is a gram-negative rod that does not ferment lactose

E.

All are true

Each of the following statements concerning Clostridium tetani is correct EXCEPT:

A.

It is a gram-positive, spore-forming rod

B.

Pathogenesis is due to the production of an exotoxin that blocks inhibitory neurotransmitters

C.

*It is a facultative organism; it will grow on a blood agar plate in the presence of room air

D.

Its natural habitat is primarily the soil

E.

All are true

Which one of the following statements concern ing immunization against diseases caused by 334.

Clostridia is CORRECT?

A.

Antitoxin against tetanus protects against botulism as well, because the two toxins share antigenic sites

B.

Vaccines containing alpha toxin (lecithinase) are effective in protecting against gas gangrene

C.

The toxoid vaccine against Clostridium difficile infection should be administered to immunocompromised patients

D.

*mmunization with tetanus toxoid induces effective protection against tetanus toxin

335.

E.

All are true

Each of the following statements concerning wound infections caused by Clostridium perfrin

336.

gens is correct EXCEPT:

A.

An exotoxin plays a role in pathogenesis

B.

Gram-positive rods are found in the exudate

C.

*The organism grows only in human cell culture

D.

Anaerobic culture of the wound site should be ordered

E.

All are true

Closcridium and Bacillus are unique among most bacteria in that they

A.

are acid-fast

B.

are Gram positive

C.

*produce Endopores

337.

D.

do not have teichoic acids

E.

are mesophiles

Choose method of staining of bacterial spores, which are formed by C. tetani and C. botulinum:

A.

Staining by mеthylene blue

B.

*Staining by Aujesko’s method

C.

Staining by Ziehl-Neelsen’s method

D.

Staining by Gram method

338.

E.

Staining by crystal violet

Laboratory assistant has to isolate Clostridium tetani, anaerobic sporeforming bacterium, from wound exudation. What will he do before inoculation of material into appropriate culture medium?

A.

he filtrates the material through cellulose filter

B.

*he heats the sample to kill asporogenous bacteria at 800C for 20 min

C.

wound discharge should be frozen before inoculation to inhibit facultative anaerobes

D.

he will not do anything before investigation

339.

E.

he heats the sample to kill vegetative forms bacteria at 600C for 5 min

Special nutrient media on which it is possible to grow anaerobic microorganisms will be next:

A.

*Zoessler, Kitt-Tarozzi's

B.

Meat - peptone agar, meat - peptone broth

C.

medium Endo's and Lewin's media

D.

The curtailed serum, meat- peptone gelatin

E.

Blood agar, serum agar

340.

Clostridium botulinum releases the most powerful biological poison which belongs to bacterial exotoxins. Choose from proposed list target cell for botulotoxin:

A.

Epithelial cell of the gut

B.

Muscle cell

C.

Motoneuron of central nervous system

D.

Sensitive neuron of spinal cord

341.

E.

Inhibiting neuron of spinal cord

The MOST important protective function of the antibody stimulated by tetanus toxoid is

A.

To opsonize the Clostridium tetani

B.

To prevent growth of the Clostridium tetani

C.

To prevent adherence of the Clostridium tetani

D.

*To neutralize the toxin of the Clostridium tetani

E.


342.


She now has a fever and severe diarrhea. Of the organisms listed, which one is MOST likely to be the

343.

cause of the diarrhea?

A.


B.


C.

Proteus mirabilis

D.


E.

Clostridium tetani.

Each of the following statements concerning Clostridium tetani is correct EXCEPT:

A.

It is a gram-positive, spore-forming rod

B.

Pathogenesis is due to the production of an exotoxin that blocks inhibitory neurotransmitters

344.

345.

C.

*It is a facultative organism; it will grow on a blood agar plate in the presence of room air

D.

Its natural habitat is primarily the soil

E.

anaerobic sporeforming bacterium

Spores are necessary to bacteria for:

A.

Survival into human and animal’s organism

B.

Reproduction

C.

*Survival in an external environment

D.

Defence from fagocytosis

E.

Defence from acid in stomack

Choose the nutrients media on which it is possible to grow anaerobic microorganisms:

A.

Endo's and Lewin's media

B.

Meat - pepton agar, meat - pepton broth

C.

*Sugar - blood agar Zoessler, Kitt-Tarozzi's medium

D.

The curtailed serum, meat-pepton gelatin

E.

Blood agar, serum agar

It is possible to cultivate obligate anaerobes on the special medium under absence of air. The 346.

347.

most reliable method to create anaerobic condition will be next:

A.

usage of thermostat

B.

*usage of anaerostat

C.

by inoculation into solid media (pour agar culture)

D.

usage of chemostat

E.

by inoculation into simple media


A.


B.


C.


D.


E.

anaerobic sporeforming bacterium

348.

349.

350.

Choose method of staining of bacterial spores, which are formed by C. perfringens:

A.

Staining by mеthylene blue

B.

*Staining by Aujesko’s method

C.

Staining by Ziehl-Neelsen’s method

D.

Staining by Gram method

E.

Staining by crystal violet

The drug of choice for antibiotic-associated pseudomembranous colitis is

A.

penicillin G

B.

*vancomycin

C.

metronidazole

D.

erythromycin

E.

a combination of a beta-lactam and an aminoglycoside

What microorganisms do not use oxygen and can actually be harmed by it?

A.

*Obligate anaerobes

B.

Facultative anaerobes

C.

Obligate aerobes

D.

Free radicals

E.

microaerophiles

351.

Successful immunization against Tetanus results in production of antibodies that prevent disease.

By what mechanism do these protective antibodies prevent Tetanus?

A.

Prevent binding of C. tetani endotoxin to monocyte receptors.

B.

Bind C. tetani flagella, prevent cell motility and access to neurons.

C.

Bind C. tetani cells and activate complement.

D.

Bind toxin receptors on neuron plasma membranes, prevent binding/entry of toxin.

E.

*Neutralize the protein exotoxin of C. tetani.

352.

A 55-year-old woman develops diplopia, one day after eating home-canned fruit. (Diplopia * double vision, from inability to coordinate the direction of gaze of the eyes.) A few hours later she develops difficulty speaking, bilateral weakness of her arms, nausea, vomiting, dizziness, blurred vision,

and dry mouth. However she is alert, oriented, and has no fever. If this is botulism, by what mechanism did Clostridium botulinum produce her signs and symptoms?

A.

Bound to Toll-like receptors and stimulated production of inflammatory cytokines.

B.

Injected proteins into neurons via a type III secretion system.

C.

*Secreted a protein toxin that enters mammalian neurons and blocks synaptic transmission.

D.

Released peptidoglycan and other inflammatory components of the cell envelope.

E.

Bacteremic spread followed by infection of multiple tissues: eyes, muscle, stomach, nervous system, salivary glands.

353.

Home-canned food is a common source of botulism in adults. What property of C. botulinum

354.

facilitates infection by this route?

A.

*Produces airborne spores not easily killed by boiling.

B.

Vegetative cells grow best at cooking temperatures.

C.

Extremely resistant to gastric acid.

D.

Thick peptidoglycan renders cells resistant to heat, cold, and drying.

E.

Surface proteins inhibit digestive hydrolases.

A patient has an abscess from which Bacterioides fragilis is isolated. Which condition is most

355.

likely to have facilitated infection by this organism?

A.


B.

*Tissue ischemia.

C.


D.


E.



During the next 12 hours the swelling increases markedly, the skin of the leg becomes discolored, and fluid-filled blisters appear on the skin. Gram stain of fluid aspirated from a blister reveals large Gram-

356.

positive rods. Which organism below is most likely to have caused this infection?

A.


B.


C.


D.

Clostridium tetani.

E.


Medical important sporeforming bacteria belong to next genus:

A.

Proteus

B.

*Clostridia

C.

Fusobacterium

357.

D.

Streptococcus

E.

Escherihia

Each of the following statements concerning Clostridia is correct EXCEPT:

A.

Pathogenic Clostridia are found both in the soil and in the normal flora of the colon

B.

Antibiotic-associated (pseudomembranous) colitis is due to a toxin produced by Clostridium difficile

C.

*Anaerobic conditions at the wound site are not required to cause tetanus, because spores will form in the presence of oxygen

D.

Botulism, which is caused by ingesting preformed toxin, can be prevented by boiling food prior to eating

E.

are Gram positive

358.

Clostridium botulinum releases the most powerful biological poison which belongs to bacterial exotoxins. Choose from proposed list target cell for botulotoxin:

A.

Epithelial cell of the gut

B.

Muscle cell

C.

*Motoneuron of central nervous system

D.

Sensitive neuron of spinal cord

359.

E.


To isolate pure culture of an obligate anaerobe from collected material you should choose the most corresponding medium from the list:

A.

Serum agar

B.

Yolk agar

C.

MPA

D.

*Robertson’s cooked meat broth or Kitt-Tarozzi medium

360.

E.

MPB with glucose

Surgeon has suspected anaerobic wound infection. To isolate causative germs collected wound discharge should be cultivated into the such medium as :

A.

Ploskirev agar

B.

*Kitt-Tarozzi medium

C.

meat peptone broth

361.

D.

Endo agar

E.

meat peptone agar

Laboratory assistant has to isolate Clostridia tetani, anaerobic sporeforming bacterium, from

362.

wound exudation. What will he do before inoculation of material into appropriate culture medium?

A.


B.


C.


D.


E.


Choose among these bacteria obligate anaerobes.

A.

Neisseria gonorrhoeae, Streptococcus pneumoniae

B.

Mycobacterium tuberculosis, Micrococcacae

C.

*Clostridium perfringens Clostridium defficile

D.

Bacillus anthracis, Brucella melitensis

363.

E.

Shigella dysenteriae, Salmonella typhi



364.


A.


B.


C.

Proteus mirabilis

D.



A.


B.


C.


D.


365.

E.

are Gram positive

Closcridium and Bacillus are unique among most bacteria in that they

A.

are acid-fast

B.

are Gram positive

C.

*produce Endopores

D.

do not have teichoic acids

E.

are mesophiles

366.

A young man develops peritonitis following abdominal trauma. During surgery foul-smelling purulent material is aspirated from the infected area. Gram stain of this material contains a mixture of

Grampositive cocci, Gram-positive rods, and many Gram-negative rods. Aerobic culture on sheep blood agar yields many colonies of enterococci and a few colonies of E. coli; culture on MacConkey agar produces only sparse colonies of E. coli. Anaerobic culture on sheep blood agar produces a few colonies of beta-hemolytic Gram-positive rods and many colonies of slender Gram-negative rods. Which organism is most likely to represent the majority of the Gram-negative rods seen when peritoneal exudate was stained?

A.

Yersinia enterocolitica

B.


C.

Clostridium tetani

D.

Yersinia pseudotuberculosis

E.


367.

A diabetic 78-year-old man develops a necrotic ulcer on his right foot. Infection spreads rapidly and there is gas in soft tissues. His foot is amputated at the ankle. Gram stain of exudate from the amputation site contains large Gram-positive rods. The bacteria grow well anaerobically, producing large ?-hemolytic colonies on sheep blood agar, but do not grow aerobically. What organism is most probable in this setting?

A.

Bacillus cereus

B.


C.

Nocardia asteroides

D.

Clostridium tetani

368.

E.



A.


B.


C.


D.


369.

E.

Binding of neurotransmitter molecules to their receptors.

A 50-year-old woman was treated for cystitis [caused by E. coli] with an oral broad-spectrum antibiotic. Three weeks later she developed abdominal pain and diarrhea. A stained smear of stool contained many neutrophils. Cultures for bacterial pathogens were negative. A serological test of stool for Clostridium difficile toxin was positive. Which of the following is most likely to have been the immediately predisposing cause of this patient’s C. difficile infection?

A.


B.


C.


D.


370.

E.


A cyanotic, listless, infant with extremely poor muscle tone is brought to the Emergency Room.

Which condition is most likely, given this presentation?

A.

*Botulism

B.

Tetanus

C.

Lyme Disease

D.

Rocky Mountain spotted fever

371.

E.

Rheumatic fever

Anaerobic bacteria may be propagated into the special media. Choose from following main requirements to such media:

A.

they should have low rH and be free from oxygen

B.

t*hey should have high rH and be free from oxygen

C.

they should contain minimal nutrients and be free from oxygen

D.

they may have any rH and nutrients

E.

All are true

372.

Each of the following statements concerning wound infections caused by Clostridium perfringens is correct EXCEPT:

A.

An exotoxin plays a role in pathogenesis

B.

Gram-positive rods are found in the exudate

C.

*The organism grows only in human cell culture

D.

Anaerobic culture of the wound site should be ordered

E.

All are true

373.

A security guard at a New Jersey Court House comes to your office with a large lesion on his left arm. It is 10 cm in diameter and ulcerated. Surrounding tissue is red and markedly swollen. The ulcer is healing to produce a black scab. A swab of the ulcer contains large Gram-positive rods. After aerobic culture on sheep blood agar these produce large alpha-hemolytic colonies. Which organism is most likely?

A.

*Bacillus anthracis

B.

Bacillus cereus

C.


D.

Clostridium perfingens

374.

E.

Clostridium tetani

An infant is brought to the emergency room, cyanotic and with poor muscle tone. Which

375.

condition is most likely given these findings?

A.


B.

Diphtheria.

C.

Anthrax.

D.

*Botulism.

E.

Tetanus.

In the United States human Tetanus is now a rare disease. Which measure below has been most

376.

important in preventing it?

A.

Vaccination of livestock, especially cattle, with a killed-organism vaccine.

B.

*Immunization of humans with a toxoid-containing vaccine.

C.

Eradication of the organism from the environment.

D.

Sewage treatment and purification of water supplies.

E.

Antibiotic treatment of contacts of patients with C. tetani infections.

Clostridium tetani produces disease by the production of a protein exotoxin. How does this toxin

377.

act?

A.

Stimulates adenyl cyclase.

B.


C.

*Blocks synaptic transmission.

D.

Cleaves ribosomal RNA.

E.

Stimulates production of cytokines.

Bipolar staining is characteristic of:

A.

*Yersinia peslis.

B.

Proteus mirabilis.

C.


378.

D.

Vibrio cholerae

E.

all are true.

Pneumonic plague can be transmitted from man to man by:

A.

*droplet infection.

B.

inoculation.

C.

ingestion.

D.

flea bite

379.

380.

E.

all are true routes.

Common reservoir host/s of Brucella melitensis is/are:

A.

*sheep and goats.

B.

cattle.

C.

pigs.

D.

dogs

E.

all are true.

Plague is transmitted by:

A.

A.sandflies.

B.

*rat fleas.

C.

mites.

D.

ticks.

E.

louse

381.

382.

Bubonic plague can be diagnosed in the laboratory by:

A.

demonstration of gram-negative coccobacilli.

B.

culture on blood agar.

C.

inoculation in guinea-pigs.

D.

inoculation in rats

E.

*all are true.

Which of the following Brucella spp. is most pathogenic for man?

A.

B. abortus

B.

*.B. melitensis.

C.

B. suis.

D.

B. canis.

383.

384.

E.

B. ovis

Bubonic plague is transmitted by:

A.

*rat flea.

B.

inhalation.

C.

ingestion.

D.

ticks

E.

all are true routes.

The name 'black death' is given to which of the following diseases?

A.

Tuberculosis.

B.

Diphtheria.

C.

*Plague.

D.

AIDS.

E.

Cholera

385.

Brucellae are transmitted to humans by:

A.

direct contact with animal tissues.

B.

ingestion of contaminated meat.

C.

ingestion of raw infected milk.

D.

direct contact with animal placenta

E.

*all are true.

386.

387.

388.

Human brucellosis is also known as

A.

Fran's disease

B.

Malta fever

C.

rabbit fever

D.

relapsing fever

E.

*undulant fever

Francisella tularensis has which portal of entry?

A.

horse-fly

B.

contact

C.

intestinal

D.

respiratory

E.

*All are correct

The bubo of bubonic plague is a/an

A.

*enlarged lymph node

B.

granuloma in the skin

C.

infected sebaceous gland

D.

tumor of lymph node

389.

E.

ulcer where the flea bite occurred

Water to be used for parenteral injection must sterilized to kill living microbes and then further purified to remove non-living bacterial components. Of those listed below, which is the most toxic?

A.


B.


C.


D.


390.

E.

Nucleic acids

If you suspect Francisella infection, you should inform the lab when sending a specimen. What is the predominant reason you need to do this?

A.

Francisella requires culture in living human cells.

B.

Francisella requires culture in living protozoa, such as amoebae.

391.

C.

Francisella although biologically Gram-negative, stains Gram-positive unless special technique is used.

D.

*Francisella is readily transmitted to laboratory workers when cultured.

E.

Francisella cannot be cultured on ‘standard media’.

In a patient with systemic febrile illness, which item in the history would indicate the highest risk for Brucella infection?

A.

*Contact with livestock or animal products.

B.

Recent travel to China.

C.

Chronic cardiopulmonary disease.

D.

Age less than two years.

E.

Drinking unpurified water from a river or stream.

392.

ways?

Brucella abortussis, a cause of undulant fever, is transmitted in all but which of the following

A.

Direct contact with infected animals

B.

Exposure to animal carcass

C.

*Exposure to animal feces

D.

Drinking unpasteurized milk

E.

No correct answer

393.

Yersinia pestis causes both the Bubonic Plague and the more deadly Pneumonic Plague. How is

Pneumonic Plague transmitted?

A.

The bite of a flea

B.

Via rodents

C.

*Air-borne

D.

Exchange of bodily fluids

E.

No correct answer

394.

395.

Which one of the following zoonotic illnesses has NO arthropod vector?

A.

Plague

B.

Lyme disease

C.

*Brucellosis

D.

Epidemic typhus

E.

All are true

Each of the following statements concerning plague is correct EXCEPT:

A.

Plague is caused by a gram-negative rod that can be cultured on blood agar

B.

Plague is transmitted to humans by flea bite

C.

The main reservoirs in nature are small rodents

D.

*Plague is of concern in many underdeveloped countries but has not occurred in the United

States since 1968

E.

All are true

396.

are all

Escherichia, Salmonella, Yersinia, and Shigella are put together in Bergey's Manual because they

A.

pathogens

B.


C.


D.

fermentative

E.

all are false

397.

A 13-year old boy develops pain and marked (10 cm.) swelling in his right inguinal lymph node accompanied by fever of 104oF. He and his family have just returned from a vacation trip to Arizona and New Mexico. Aspirate from the node contains Gram-negative rods. A direct immunofluorescent assay on the aspirate provides a definitive diagnosis. The child is (successfully) treated with streptomycin, and the aspirate is sent for culture to the CDC. Culture yields pale colonies on

398.

MacConkey agar. What is the most probable pathogen?

A.

*Yersinia pestis.

B.

Helicobacteri pylori.

C.

Franciscella tularensis.

D.

Coxiella burnetii.

E.


The following are characterized by bradycardia except

A.

Typhoid fever

B.

*Brucellosis

C.

Leptospirosis

D.

Yellow fever

E.

No correct answer

399.

A 34-year old person has rapidly developing cough, dyspnoea, expectoration ana blood-tinged sputum, he is febrile, cyanosed and toxic. Chest examination reveals crepitations and rhonchi. The most likely diagnosis is

A.

Legionella pneumonia

400.

401.

B.

*Pneumonic plague

C.

Septicaemic plague

D.

Pulmory tuberculosis

E.

No correct answer

Milk ring test

A.

*Brucellosis

B.

Bacteroides

C.

Tuberculosis

D.

Salmonellosis

E.

Diphtheria

Bubo is seen in

A.

typhoid fever

B.

*Plague

C.

Lymphoma

D.

Filariasis

E.

Scarlet fever

402.

403.

404.

Which is not a zoonotic disease

A.

Rabies

B.

Anthrax

C.

Plague

D.

Brucellosis

E.

*All are correct

Undulant fever is caused by

A.

Bartonella

B.

*Brucella melitensis

C.

Bordetella

D.

Borrelia recurrentis

E.

Streptococci

Granuloma with stellate abscess

A.

TB

B.

*Tularemia

C.

Sarcoidosis

D.

Staphylococcus

405.

E.

Streptococcus

Organism most likely to cause "fevert of unknown origin" in a farmer who raises goats

A.

*Brucella melitensis

B.

Clostridium novyi

C.

Histoplasma capsulatum

D.

Mycobacterium tuberculosi

E.

No correct answer

Which of the following describes enteric bacteria? 406.

A.

Gram-positive cocci

B.

Gram-negative cocci

C.

Gram-positive rods

D.

*Gram-negative rods

E.

Gram-positive spirals

407.

Bubonic plagues (Y. pestis) is characterized by and pneumonic plague (Y. pestis) is characterized by

408.

A.

*A 7-day incubation period; A 3-day incubation period

B.

A > 90% mortality rate; A >75% mortality rate

C.

Pulmonary disease; A painful bubo (inflammation of the lymph nodes)

D.

Aerosol spreading from person-to-person; Flea bites

E.

Septicemia; Cutaneous hemorrhagic necrosis

Which of the following is the natural reservoir for urban plague (Y. pestis)?

A.

Cows

B.

Rabbits

C.

Turtles

409.

D.

*Rats

E.

Mosquitoes

Which of the following is NOT a natural reservoir for sylvatic plague (Y. pestis)?

A.

Squirrels

B.

Rabbits

C.

*Livestock

D.

Rats

E.

Domestic cats

Brucella and Francisella are examples of what kind of disease, where they can be transmitted 410.

411.

from animal to human?

A.

Nosocomial

B.

Water-borne

C.

Blood-borne

D.

*Zoonosis

E.

Opportunistic

What is the primary virulence factor of the intracellular parasite F. tularensis?

A.

cAMP inducing toxin

B.

*Capsule

C.

Spore

412.

D.

Teichoic acid

E.

Type III secretion system

Which of the following carriers of F. tularensis is the most common for transmission to a human host?

A.

Domestic cats

B.

Birds

C.

Ticks

413.

D.

Domestic cats and dogs

E.

*Rabbits and ticks

Which of the following locations is the least likely for F. tularensis (tularemia) to be found?

A.

Arkansas

B.

Oklahoma

C.

Missouri

D.

Pennsylvania

414.

E.

*Australia

What growth factors are required for F. tularensis?

A.

Heme (X)

B.

NAD (V)

C.

Heme and NAD (X and V)

D.

*Cysteine

415.

E.

Cysteine and heme (X)

A doctor is struggling to diagnose a woman’s flulike illness. She complains of a fever that rises during the day and peaks after dinner (undulant fever), fatigue, spinal tenderness, and loss of appetite.

Her lymph nodes are enlarged in physical exam. The doctor has trouble narrowing down the possible etiologies until he hears that the tasted goat cheese at a French village a month before the onset of her symptoms. Which of the following is the most likely cause?

A.


B.

*Pseudomonas aeruginosa

C.


D.

Francisella tularensis

E.

Brucella species

416.

Which of the following is NOT true (in general) for Clostridium?

A.

*Gram-negative

B.

Bacilli shaped

C.

Spore-forming

D.

Obligate anaerobes

E.

Unable to reduce sulfate to sulfite

417.

A teenage girl enters the emergency room suffering painful muscle spasms. Throughout her examination, she sustains a facial sneer, a stiff arched back, and clamped palms. Her father is anxious about the fact that she has also experienced difficulty eating, probably due to a stiff jaw. The father affirms that her daughter is usually quite active and boasts how, a week ago, she continued a soccer game even after falling on a nail in the field. Which of the following is the most likely cause?

A.

C. difficile

B.

C. perfingens

C.

C. septicum

D.

C. botulinum

418.

E.

*C. tetani

A woman straggles into the emergency room with a marked paralysis of her upper body. She describes the paralysis as a weakness that began in her neck and spread to her arms. She also complains of blurred double vision and requests water to soothe her dry throat. Though she has no fever, she appears quite dizzy and her eyelids are drooping. The day before, she returned from a camping trip where she insists she maintained good hygiene, limiting her diet to canned food only. Which of the following is the most likely cause?

A.

C. difficile

B.

C. perfingens

C.

C. septicum

D.

*C. botulinum

E.

C. tetani

419.

An old woman comes to the doctor with a fever and loose bowels. Her diarrhea occurs in tremendous volumes, she complains, though she doesn’t remember seeing blood. She has an unremarkable recent past medical history, except for an infection a few weeks earlier that was treated with clindamycin. Sigmoidoscopy of her colon reveals yellow-white plaques which the doctor predicted after analyzing her stools for toxins. Which of the following is the most likely cause?

A.

*C. difficile

B.

C. perfingens

C.

C. septicum

D.

C. botulinum

E.

C. tetani

420.

A man enters the emergency room claiming to have been stabbed two days earlier. Muscles in his arm hurt, and on palpation small air bubbles are felt below the skin. The wound area exudes a blackish, ill-smelling fluid that generates a crackling sound when touched. The patient has a fever, a low blood pressure, marked tachycardia, and urina very little since his injury. The doctor decides to amputate the arm, as well as monitor the patient for shock and renal failure Which of the following is

421.

the most likely cause?

A.

C. difficile

B.

*C. perfingens

C.

C. septicum

D.

C. botulinum

E.

C. tetani

Which of the following is a cause of nontraumatic myonecrosis and often exists in patients with

422.

occult colon cancer, acute leukemia, or diabetes?

A.

C. difficile

B.

C. perfingens

C.

*C. septicum

D.

C. botulinum

E.

C. tetani

Which of the following is associated with Floppy Baby Syndrome?

A.

C. difficile

B.

C. perfingens

C.

C. septicum

423.

D.

*C. botulinum

E.

C. tetani

Which of the following is associated with Pseudomembrane Colitis (PMC)?

A.

*C. difficile

424.

425.

426.

B.

C. perfingens

C.

C. septicum

D.

C. botulinum

E.

C. tetani

Which of the following describes the effect of tetanus toxin?

A.

*Unregulated excitatory synaptic activity in the motor neurons

B.

Blocks neurotransmission at peripheral cholinergic synapses

C.

Induces depolymerization of actin with loss of cellular cytoskeleton

D.

Produces chemotaxis; induces cytokine production with hypersecretion of fluid; produces hemorrhagic necrosis

E.

All are correct

Which of the following describes the effect of botulinum toxin?

A.

Unregulated excitatory synaptic activity in the motor neurons

B.

*Blocks neurotransmission at peripheral cholinergic synapses

C.


D.


E.

All are correct

Which of the following describes the effect of C. difficile toxin?

A.

Unregulated excitatory synaptic activity in the motor neurons

B.

Blocks neurotransmission at peripheral cholinergic synapses

C.


D.


E.

*All are correct

A mother brings her 12-year-old son to your office because he has a skin lesion on his back. It is 427.

20 cm in diameter, with a red inflamed border and a red center, with a paler ring between the red areas.

The mother says it has expanded rapidly over the last few days. Which of the following would be most likely to cause such a lesion?

A.

Rickettsia rickettsii

B.

Treponema pallidum

C.

*Borrelia burgdorferi

D.

Chlamydia psittaci

428.

E.


A 16-year-old boy has a skin lesion on his back. It is 20 cm in diameter, with a red inflamed border and a red center, with a paler ring between the red areas. He says it has expanded rapidly over the

429.

last few days after tick bite. Which of the following would be most likely to cause such a lesion?

A.


B.


C.

Treponema pallidum

D.

Chlamydia psittaci

E.


What vectors are spread an epidemic typhus?

A.

Rat fleas.

B.

Dog ticks.

C.

*Human body lice.

D.

Mosquitos.

E.

Deer ticks.

430.

A patient is diagnosed with pelvic inflammatory disease (PID), you suspect caused by

Chlamydia trachomatis. If you wished to confirm C. trachomatis, which test below should you use?

A.

Culture of urine on broth-based agar at 20?C.

B.

Culture of cervical exudate on chocolate agar in elevated CO2.

C.

Microscopic examination of a stained smear of peripheral blood.

431.

D.

*Gram stain of exudate from the cervix.

E.

PCR-based nucleic-acid amplification test of a cervical swab.

Which of the following staining techniques cannot be used for T. pallidum?

A.

*Gram staining.

432.

433.

B.

Giemsa staining.

C.

Silver impregnation staining.

D.

Imunofluorescence staining.

E.

Burri staining.

Louse-borne relapsing fever is caused by:

A.

*Borrelia recurrentis.

B.

B. duttoni.

C.

B. burgdorferi.

D.

B. parkeri.

E.

B. persica

Which of the following bacteria dies quickly after drying?

A.

Mycobacterium tuberculosis.

B.


C.


D.

Bacillus anthracis

E.

*Treponema pallidium

434.

435.

436.

In which of the following sexually transmitted diseases, ulcer/s is/are painless?

A.

*Syphilis.

B.

Chancroid.

C.

Herpes genitalis.

D.

All are true.

E.

No correct answer

Treponema pallidum can be cultivated in:

A.

*rabbit testes.

B.

blood agar medium.

C.

chocolate agar medium.

D.

Thayer-Martin medium.

E.

Kitt-Tarozi medium

Relapses in relapsing fever occur due to:

A.

*antigen variation in bacteria.

B.

increased toxin production by bacteria.

C.

increased invasiveness of bacteria.

D.

super infection with viruses.

437.

E.

increased fermentative activity of bacteria

Human body louse is responsible for transmission of which of the following diseases?

A.

*Epidemic typhus.

B.

Murine typhus.

C.

C.Rickettsialpox.

D.

Q fever.

E.

Typhi fever

Sterols are present in the cytoplasmic membrane of: 438.

A.

*Mycoplasma.

B.

Bacillus.

C.

Clostridium.

D.

Proteus.

E.

Rickettsia

439.

Which of the following bacteria is/are implicated as causative agent/s of non-gonococcal urethritis?

440.

A.

Chlamydia trachomatis.

B.

Ureaplasmau urealyticum.

C.

Mycoplasma hominis.

D.

Herpes virus 2

E.

*All are true

Appearance of a hard chancre is characteristic of:

A.

*primary syphilis.

B.

secondary syphilis.

C.

latent syphilis.

441.

442.

443.

444.

445.

446.

447.

448.

449.

450.

D.

tertiary syphilis.

E.

complication of syphilis

Lyme disease is caused by:

A.

Borrelia recurrenlis.

B.

B. dutioni.

C.

*B. burgdorferi.

D.

B. hermsii

E.

B. persica

Treponema pallidum is cultured in/on

A.

blood agar

B.

eggs

C.

horse serum

D.

*rabit testis

E.

serum broth

Formation of a gumma is

A.

a damaged aorta

B.

a damaged liver

C.

*a syphilitic tumor

D.

the primary lesion of syphilis

E.

the result of congenital syphilis

The treatment of choice for syphilis is:

A.

antiserum

B.

aurum drug

C.

penicillin

D.

*sulfa drugs

E.

tetracycline

All the treponematoses are not veneral disease except:

A.

bejel

B.

pinta

C.

yaws

D.

*syphilis

E.

All are true

Lyme disease is caused by ______ and spread by ______.

A.

Borrelia recurrentis, lice

B.

*Borrelia burgdorferi, ticks

C.

Borrelia burgdorferi, chiggers

D.

Borrelia hermsii, ticks

E.

Borrelia recurrentis, ticks

Epidemic Relapsing fever is spread by

A.

*lice

B.

ticks

C.

flea

D.

mosquites

E.

animal urine

Endemic Relapsing fever is spread by

A.

lice

B.

*ticks

C.

flea

D.

mosquites

E.

animal urine

Rickettsias and chlamydias are similar in being

A.

carried by arthropod vectors

B.

free of a cell wall

C.

*obligate intracellular bacteria

D.

produce exotoxin

E.

the cause of eye infections

Which of the following is/are an arthropod vector of rickettsioses?

451.

452.

A.

flea

B.

louse

C.

tick

D.

*all are true

E.

no correct answer

Chlamydia trachomatis can attacks which structure(s)?

A.

eye

B.

urethra

C.

fallopian tubes

D.

lungs

E.

*all of these

Ornithosis is a _____ infection associated with ______

A.

rickettsial, parrots

B.

chlamydial, mice

C.

*chlamydial, birds

D.

rickettsial, flies

453.

E.

chlamydial, rats

Mycoplasmas demage next structure of host cells.

A.

nucleus

B.

cell walls

C.

ribosomes

D.

*cell membranes

E.

mitochondria

454.

You suspect Chlamydia infection in a sexually-active young woman. Which test would be most likely to provide results which would confirm this diagnosis?

A.

Agglutination test for anti-cardiolipin antibodies.

B.

*PCR test of nucleic acids present in a urine sample.

C.

Test of a blood sample for ‘cold agglutinins”.

D.

Gram-stained smear of discharge from the cervix.

455.

E.

Culture of exudate from the cervix on Thayer-Martin agar.

A mother is worried that the child may have contracted Lyme disease. Which finding would most strongly suggest that she is correct?

A.

A disseminated rash, with small papular erythematous lesions.

B.

An ulcer and edema at the site of the tick bite.

C.

A lesion at the site of the tick bite that develops a thick, black, crusted, scab.

D.

*A “bull’s-eye” lesion with erythematous periphery and central clearing.

456.

E.

A sparse red macular rash, on the palms and soles only.

A 25-year-old female presented with a three-day history of fever, headache and a non-productive cough. X-rays show bilateral diffuse lung infiltrates. Culture of a throat swab (on sheep blood and chocolate agars) revealed only “normal oral flora”. Penicillin G was prescribed and the patient sent home. Her illness did not respond to this antibiotic. She was then successfully treated with erythromycin. Which organism is most likely to have caused her illness?

A.

*Mycoplasma pneumoniae.

B.


C.


D.


457.

E.


A patient has a positive Rapid Plasma Reagin (RPR) test for ‘non-treponemal antibodies’. A test for specific anti-treponemal antibodies is positive but the patient has no rash, genital lesions, inflammation, or discharge. Which conclusion best follows from these findings?

A.

The patient does not require antibiotic treatment; absence of symptoms indicates that the positive

RPR is a ‘biological false positive”.

B.

The patient has Syphilis, but does not require antibiotic treatment, because infections with

Treponema pallidum normally resolve spontaneously.

C.

The patient has Syphilis, but the diagnosis should be confirmed by culture before antibiotictreatment is started.

D.

*The patient has Syphilis, and should be treated with Penicillin G

458.

E.

No correct answer

Chlamydia trachomatis may be cultured on monolayers of human cells. If infected cells were

459.

examined by staining and light microscopy, what would you be most likely to observe?

A.

*A membrane-bounded inclusion body, within the nucleus.

B.

A membrane-bounded inclusion body, within the cytoplasm.

C.

Rod shaped Gram-positive bacilli, free within the cytoplasm.

D.

Gram-negative cocci, within the lumen of the endoplasmic reticulum.

E.

Cyst forms inside lysosomes.

In August, a young man presents with a history of fever for 1 week and a red rash which extends to the palms and soles. IgM titer to Rickettsia rickettsii is 1:640. From which vector was this infection most likely to have been acquired?

A.

*Dog tick.

B.

Mosquito of the genus Anopheles.

C.

Blood-sucking sandfly.

D.

Flea.

E.

Human body louse.

460.

The cell tropism of the genus Rickettsia determines the type of disease produced. Which phrase best describes Rickettsial disease?

A.

Encephalitis

B.

Meningitis.

C.

Myocarditis.

D.

Myositis.

E.

*Vasculitis.

461.

The symptom of secondary syphilis is

A.

neurological problems

B.

giant lesions affecting many internal organs

C.

a hard-based, painless chancre

D.

*a rash covering all parts of the body

E.

All are true

462.

463.

464.

Syphilis is caused by which of the following?

A.

Helicobacter pylori

B.

Proteus mirabilis

C.

*Treponema pallidum

D.

Serratia marcesans

E.

Treponema Vincentii

Borellia burgdorferi causes which disease?

A.

*Lyme Disease

B.

Rocky Mountain Spotted Fever

C.

Hanta

D.

Rabies

E.

Relapsing fever

How is leptospirosis, caused by Leptospira interrogans, transmitted?

A.

Tick bite

B.

*Contaminated urine in food or water

C.

Undercooked meat

D.

Inhaled aerosol

465.

E.

louse feces

Rickettsia rickettsii causes Rocky Mountain Spotted fever when transmitted by tick bite. When transmitted by lice, it causes:

A.

*Epidemic typhus

B.

Scarlet fever

C.

Hydrocephalus

D.

Rheumatic fever

466.

E.

No correct answer

Which of the following is NOT true about Mycoplasma hominis?

A.

Synonymous with Ureaplasma urealyticum

B.

More prevalent in late summer/early fall

C.

*Vaccine uses conjugated polysaccharide B

D.

Is endemic worldwide

E.

No correct answer

What is the first symptom of Treponema pallidum? 467.

A.

*Chancre at infection site

B.

Bullseye rash

C.

Butterfly rash

D.

Vaginal discharge

E.

No correct answer

468.

469.

Which one of the following diseases is BEST diagnosed by serologic means?

A.

*Q fever

B.

Pulmonary tuberculosis

C.

Gonorrhea

D.

Actinomycosis

E.

All are true

Which one of the following organisms principally infects vascular endothelial cells?

A.

Salmonella typhi

B.

*Rickettsia typhi

C.


470.

D.

Coxiella burnetii

E.

All are true

Each of the following statements concerning chlamydiae is correct EXCEPT:

A.

Chlamydiae are strict intracellular parasites because they cannot synthesize sufficient ATP

B.

Chlamydiae possess both DNA and RNA and are bounded by a cell wall

C.

trachomatis has multiple serotypes, but C psittaci has only one serotype

D.

*Most chlamydiae are transmitted by arthropods

471.

E.

All are true

A 25-year-old man complains of a urethral discharge. You perform a Gram stain on a specimen of the discharge and see neutrophils but no bacteria. Of the organisms listed, the one MOST likely to

472.

cause the discharge is

A.

Treponema pallidum

B.

*Chlamydia trachomatis

C.

Candida albicans

D.

Coxiella burnetii

E.

All are true

Each of the following statements concerning Treponema is correct EXCEPT:

A.

*T. pallidum produces an exotoxin that stimulates adenylate cyclase

B.

T. pallidum cannot be grown on conventional laboratory media

C.

Treponemes are members of the normal flora of the human oropharynx

D.

Patients infected with T. pallidum produce antibodies that react with beef heart cardiolipin

E.

All are true

473.

Each of the following statements concerning chlamydial genital tract infections is correct

EXCEPT:

A.

*Infection can be diagnosed by finding anti-chlamydial antibody in a serum specimen

B.

Infection can persist after administration of penicillin

C.

Symptomatic infections can be associated with urethral or cervical discharge containing many

474.

475.

polymorphonuclear leukocytes

D.

There is no vaccine against these infections

E.

All are true

Each of the following statements concerning Chlamydia trachomatis is correct EXCEPT:

A.

It is an important cause of nongonococcal urethritis

B.

It is the cause of lymphogranuloma venereum

C.

*It is an important cause of subacute bacterial endocarditis

D.

It is an important cause of conjunctivitis

E.

All are true

Which one of the following types of organisms is NOT an obligate intracellular parasite and therefore can replicate on bacteriologic media?

476.

A.

Chlamydia

B.

*Mycoplasma

C.

Adenovirus

D.

Rickettsia

E.

All are true

The soil is the natural habitat for certain microorganisms of medical importance. Which one of the following is LEAST likely to reside there?

A.

Clostridium tetani

B.

Mycobacterium intracellular

C.

Bacillus anthracis

D.


E.

All are true

477.

478.

Each of the following statements concerning the VDRL test for syphilis is correct EXCEPT:

A.

*The antigen is composed of inactivated Treponema pallidum

B.

The test is usually positive in secondary syphilis

C.

False-positive results are more frequent than with the FTA-ABS test

D.

The antibody titer declines with adequate therapy

E.

All are true

Each of the following statements concerning epidemic typhus is correct EXCEPT:

A.

The disease is characterized by a rash

B.

The Weil-Felix test can aid in diagnosis of the disease

C.

The disease is caused by a rickettsia

D.

*The causative organism is transmitted from rodents to humans by a tick

479.

E.

All are true

Each of the following statements concerning spirochetes is correct EXCEPT:

A.

Species of Treponema are part of the normal flora of the mouth

B.

Species of Borrelia cause a tick-borne disease called relapsing fever

C.

*The species of Leptospira that cause leptospirosis grow primarily in humans and are usually transmitted by human-to-human contact

D.

Species of Treponema cause syphilis and yaws

E.

All are true

480.

Each of the following statements concerning infection with Chlamydia psittaci is correct

EXCEPT:

A.

C psittaci can be isolated by growth in cell culture and will not grow in blood agar

B.

The organism appears purple in Gram-stained smears of sputum

C.

The infection is more readily diagnosed by serologic tests than by isolation of the organism

481.

D.

*The infection is more commonly acquired from a nonhuman source than from another human

E.

All are true

Ticks are vectors for the transmission of each of the following diseases EXCEPT:

A.

Rocky Mountain spotted fever

B.

*epidemic typhus

C.

tularemia

D.

Lyme disease

482.

E.

All are true

Each of the following statements concerning pneumonia caused by Mycoplasma pneumoniae is correct EXCEPT:

A.

The disease is associated with a rise in the titer of cold agglutinins

B.

*The disease occurs primarily in immunocompetent individuals

C.

The disease is one of the "atypical" pneumonias

D.

The organism cannot be cultured in vitro because it has no cell wall

483.

E.

All are true

Each of the following statements concerning Q fever is correct EXCEPT:

A.

*Rash is a prominent feature

B.

It is transmitted by respiratory aerosol

C.

Farm animals are an important reservoir

D.

It is caused by Coxiella burnetii

E.

All are true

484.

Lyme disease is caused by a

A.

Chlamydiae

B.

Rickettsiae

C.

*a spirochete

D.

enteric bacteria

E.

all are false

485.

Borrelia is classified with the spirochetes because it

A.

is aerobic

B.

*possesses an axial filament

C.

is a rod

D.

is a pathogen

E.

none of answers

486.

An 8-year-old boy living in a wooded area of Virginia suddenly developed fever, headache, and myalgia. On physical exam, a rash was noted on his limbs and trunk. Lesions of the rash were red and a few mm in diameter. No organisms were isolated from several blood cultures. The child was treated with tetracycline and recovered. Serological tests of acute and convalescent serum samples from the

487.

child are most likely to reveal an increase in antibody titer to...

A.

Borrelia burgdorferi.

B.

Chlamydia pneumoniae.

C.


D.

Yersinia pestis.

E.

*Rickettsia rickettsii.

A 15-year-old female presented with a three-day history of fever, headache and a non-productive cough. Penicillin was prescribed and the patient was sent home. Her illness did not respond to this antibiotic. Gram stain and culture of the patient's sputum and a throat swab revealed only 'normal oral flora'. She was then successfully treated with erythromycin. Which organism below is most likely to

488.

have caused her illness?

A.


B.


C.


D.

Corynebacterium diphtheriae.

E.


Which of the following bacteria can be successfully cultured on cell-free medium?

A.


B.

Coxiella burnetii.

C.

Mycobacterium leprae.

489.

D.


E.

Rickettsia prowazekii.

Indicate disease caused by Treponema pallidum:

A.

Weil syndrome (icterohemorrhagic fever), canicola fever

B.

Endemic relapsing fever

C.

Lyme disease

D.

*Syphilis

490.

E.

Enteric fever

Indicate disease caused by Leptospira interrogans:

A.

*Weil syndrome (icterohemorrhagic fever), canicola fever

B.


C.

Lyme disease

D.

Syphilis

E.

Enteric fever

491.

Indicate disease caused by Borrelia burgdorferi:

A.


B.


C.

*Lyme disease

D.

Syphilis

E.

Enteric fever

492.

Indicate disease caused by Borrelia recurrentis:

493.

494.

A.


B.

*Endemic relapsing fever

C.

Lyme disease

D.

Syphilis

E.

Enteric fever

Which of the following is true for visualizing spirochete?

A.

They can be viewed without significant magnification (e.g. 10x)

B.

They can be viewed with Gram stain

C.

They can be viewed with Giemsa stain

D.

*They require special analysis such as dark field illumination or silver stain

E.

They are eucaryotes

Which of the following groups of people is most at risk for contracting T. pallidum?

A.

Pregnant mothers

B.

Cystic fibrosis patients

C.

*Sexually active patients

D.

Elderly patients

495.

E.

Anyone (spread through contact with inanimate objects, such as toilet seats)

The tissue destruction and lesions observed in syphilis are primarily a consequence of which of the following?

A.

Bacterial capsule

B.

Bacterial endoflagellum

C.

Bacterial overgrowth

D.

Bacterial hyaluronidase

496.

E.

*Host immune response

What stage of syphilis is characterized by disseminating rash, alopecia, lymphadenopathy, and flulike symptoms.

A.

Primary

B.

*Secondary

C.

Tertiary

D.

Congenital

E.

No correct answer

497.

Children born with congenital syphilis often exhibit Hutchinson Triad, which includes deafness, blindness, and centrally notched teeth. If the mother has been exposed to Chlamydia, syphilis, or gonorrhea, the newborn may receive a prophylactic antibiotic for their:

A.

Ears

B.

*Eyes

C.

Nose

D.

Mouth

E.

Systemic antibiotic (via IV)

498.

499.

What is characteristic of primary syphilis?

A.

Painful chancre

B.

*Painless chancre

C.

Several painful ulcers in genital region

D.

Several painless ulcers in genital region

E.

Disseminating rash on entire body, soles, and palms

Of the following organisms that can cross the placenta, which of the following is associated with

500.

congenital CN VIII deafness, mulberry molars, saddle nose, blindness, deafness, and cardiovascular problems?

A.

Toxoplasma gondii

B.

Rubella

C.

Cytomegalovirus

D.

Herpes, HIV

E.

*Syphilis

Which of the following is/are used to confirm nontreponemal assays?

A.

Venereal Disease Research Laboratory (VDRL) test

B.

Rapid Plasma Reagin (RPR) test

C.

Agglutination test

D.

*Treponema pallidum particle agglutination (TP-PA) test

E.

All are true

501.

502.

503.

Indicate microbe which has sexual mode of transmission:

A.

*Treponema pallidum

B.


C.

Borrelia burgdorferi

D.

Leptospiras interrogans

E.

Treponema vincentii

Indicate microbe which uses ticks for mode of transmission:

A.

Treponema pallidum

B.


C.


D.


E.

Treponema vincentii

Indicate microbe which uses ticks for mode of transmission:

A.

Treponema pallidum

B.


C.


D.


E.

Treponema vincentii

Indicate microbe which uses rodents, dogs, fish, birds for mode of transmission: 504.

A.

Treponema pallidum

B.


C.


D.

*Leptospiras interrogans

E.

Treponema vincentii

505.

506.

Indicate microbe which uses human-to-human for mode of transmission:

A.

Treponema pallidum

B.

*Borrelia recurrentis

C.


D.


E.

Treponema vincentii

Which of the following is an early clinical sign of Lyme Disease and not a late sign?

A.

Musculoskeletal disease (e.g. migratory myalgias, transient arthritis)

B.

Nervous system disease (e.g. Bell palsy, encephalopathy)

C.

Cardiovascular involvement (e.g. AV nodal block)

D.

*Erythema chronicum migrans (ECM)

E.

Acrodermatitis chronicum atrophicans (ACA)

Which of the following locations within the United States has the highest reported cases of 507.

508.

Leptospira infection each year?

A.

Minnesota

B.

Pennsylvania

C.

New York

D.

Wisconsin

E.

*Hawaii

A farmer comes to the ER with a 1-week history of flu-like symptoms with photophobia. His severe headache, cough, and myalgias suggest to the physician some kind of respiratory infection.

However, more careful physical exam reveals conjunctival suffusion and macular rash. Lab findings include elevated serum bilirubin, alkaline phosphatase, aminotransferase, and creatine phosphokinase.

With this clinical picture and lab results, the physician prescribes penicillin G immediately. His suspicions are confirmed later when a spirochete is isolated from the patient’s blood. Which of the following is the most likely cause?

A.

Treponema pallidum

B.

*Leptospira interrogans

C.


D.


E.

Treponema vincentii

509.

Mycoplasma pneumoniae (Eaton agent) are unique among bacteria because their cell membrane contains sterols and they do not have which of the following?

A.

?-lactam antibiotic resistance

B.

Flagella

C.

Endotoxin

D.

Capsule

510.

E.

*Cell wall

Which of the following is associated with Ureaplasma?

A.

*Genitourinary tract infection

B.

Atypical pneumonia

C.

Tracheobronchitis

D.

Influenza-like illness

E.

Upper respiratory tract infection

511.

Mycoplasma pneumoniae is a common cause of atypical pneumonia (walking pneumonia) and chest x-ray often looks worse than symptoms suggest. Which of the following groups of people is the most commonly affected?

A.

Elderly

B.

Middle-aged adults

C.

*School-age children

D.

Neonates

E.

Pregnant mothers

512.

Which of the following tests is the most useful currently as an initial laboratory test, has about

65% sensitivity, and has specificity that cross-reacts to other organisms (e.g., Epstein-Barr virus, cytomegalovirus, adenovirus)?

A.

Microscopy

B.

Molecular diagnosis

C.

Complement fixation

D.

Enzyme immunoassays

E.

*Cold hemagglutination

513.

Which of the following is an organism that prefers to live inside a host cell but may live outside a host cell?

A.

Extracellular pathogen

B.

Intracellular pathogen

C.

Obligate intracellular parasite

D.

Obligate extracellular parasite

E.

*Facultative intracellular parasite

514.

515.

516.

517.

Rickettsia, an aerobic Gram-negative rod, is which of the following?

A.


B.

*Obligate intracellular parasite

C.


D.

Facultative intracellular parasite

E.

No correct answer

What disease does Rickettsia rickettsii cause?

A.

*Rocky Mountain spotted fever (Western hemisphere)

B.

Epidemic typhus (Worldwide)

C.

Scrub typhus (Asia, Oceania)

D.

Q fever (Worldwide)

E.

Relapsing fever

What disease does Rickettsia prowazekii cause?

A.

Rocky Mountain spotted fever (Western hemisphere)

B.

*Epidemic typhus (Worldwide)

C.


D.

Q fever (Worldwide)

E.

Relapsing fever

What disease does Orientia tsutsugamushi cause?

A.


B.


518.

519.

520.

521.

522.

523.

524.

525.

526.

C.

*Scrub typhus (Asia, Oceania)

D.

Q fever (Worldwide)

E.

Enteric fever

What disease does Coxiella burnetii cause?

A.


B.


C.


D.

*Q fever (Worldwide)

E.

Scarlet fever

Match the with Rickettsia: Rocky Mountain spotted fever (Western hemisphere)

A.

Orientia tsutsugamushi

B.

Coxiella burnetii

C.

*Rickettsia rickettsii

D.

Rickettsia prowazekii

E.

No correct answer

Match the Epidemic typhus (Worldwide) with Rickettsia:

A.


B.

Coxiella burnetii

C.


D.

*Rickettsia prowazekii

E.

No correct answer

Match the Scrub typhus (Asia, Oceania) with Rickettsia:

A.

*Orientia tsutsugamushi

B.

Coxiella burnetii

C.


D.


E.

No correct answer

Match the Q fever (Worldwide) with Rickettsia:

A.


B.

Coxiella burnetii

C.


D.


E.

*No correct answer

Match the following vector – cattle, sheep, goats – with Rickettsia

A.


B.

Coxiella burnetii

C.


D.


E.

Bartonella quintana

Match the following vector – flying squirrels, louse – with Rickettsia

A.


B.

Coxiella burnetii

C.


D.


E.

Bartonella quintana

Match the following vector – dogs, rodents, wood/dog tick – with Rickettsia

A.


B.

Coxiella burnetii

C.


D.


E.

Bartonella quintana

Match the following vector – chiggers, red mites – with Rickettsia

A.

*Orientia tsutsugamushi

B.

Coxiella burnetii

C.


D.


E.

Bartonella quintana

527.

Match Orientia tsutsugamushi with the vector:

A.

Cattle, sheep, goats

B.

Flying squirrels, louse

C.

Dogs, rodents, wood/dog tick

D.

*Chiggers, red mites

E.

No correct answer

528.

Match Coxiella burnetii with the vector:

A.

*Cattle, sheep, goats

B.


C.


D.

Chiggers, red mites

E.

No correct answer

529.

530.

Match Rickettsia prowazekii with the vector:

A.


B.

*Flying squirrels, louse

C.


D.

Chiggers, red mites

E.

No correct answer

Match Rickettsia rickettsii with the vector:

A.


B.


C.

*Dogs, rodents, wood/dog tick

D.

Chiggers, red mites

531.

E.

No correct answer

A 10-year-old boy in Virginia presents with a rash, fever, and severe headache that began several days ago. The rash began on his palms and soles and has now spread to his trunk. His pediatrician also notes conjunctival redness, and lab studies show proteinuria. The boy’s history is significant for a hike in the woods a week ago. The child is given tetracycline and his diagnosis is confirmed by a Weil-Felix test. Which of the following is the most likely cause?

A.


B.

Coxiella burnetii

C.


D.


532.

E.

Rickettsia acari

A cattle farmer goes to the doctor complaining of mild cough and fever. He says that the fever began abruptly several days ago. His occupation as cattle slaughterer leads the doctor towards a diagnosis, and tetracycline is administered. The diagnosis is confirmed by serology and a negative Weil-

Felix test. Which of the following is the most likely cause?

A.


B.

*Coxiella burnetii

C.


D.


E.

Rickettsia sibirica

533.

A Kosovo refugee sees a volunteer camp doctor complaining of a rash spreading outward from his trunk but sparing his palms and soles. Two days ago, he experiences abrupt onset of fever, headaches, and confusion. On physical exam, the doctor discovers lice in the man’s hair. The doctor treats with a delousing regimen and tetracycline. Were he at a hospital, he might confirm the diagnosis with a Weil-Felix test. Which of the following is the most likely cause?

A.


B.

Coxiella burnetii

C.


D.


E.

Bartonella quintana

534.

The Chlamydiaceae life cycle has elemental bodies (EBs) that are ____ and reticulate bodies

(RBs) that are ____.

A.

Metabolically active and infection; Metabolically inactive and noninfectious

B.

*Metabolically inactive and infection; Metabolically active and noninfectious

C.

Metabolically active and noninfection; Metabolically inactive and infectious

D.

Metabolically inactive and noninfection; Metabolically active and infectious

535.

E.

No correct answer

In the life cycle of Chlamydiaceae, ____ bind to cell receptors triggering endocytosis. ____ inhibit lysosome fusion and form ___, which replicate by binary fission and form ____ that cause the

536.

cell to lyse.

A.

*EBs; EBs; RBs; EBs;

B.

EBs; RBs; RBs; EBs;

C.

RBs; EBs; EBs; RBs;

D.

RBs; RBs; EBs; RBs;

E.

RBs; RBs; EBs; EBs;

Chlamydia uses ATP for energy in order to construct DNA and proteins as well as encoding their

537.

own ribosomes. This makes Clamydia which of the following?

A.


B.

*Obligate intracellular parasite

C.


D.

Facultative intracellular parasite

E.

No correct answer

A woman is brought to the ER complaining of vaginal discharge and RUQ abdominal pain. On history, the patient reports having many sexual partners. Pelvic exam reveals cervical motion tenderness, and labs of vaginal discharge detect numerous PMNs but no organisms on Gram stain. The doctor makes a diagnosis based on these findings and administers doxycycline and ceftriaxone. Later, surgeons, concerned about the patient’s abdominal pain, rule out cholecystitis by imaging, but laparoscopy reveals adhesions around the patient’s liver capsule. Which of the following is the most likely cause?

A.

Chlamydia psittaci

B.

*Clamydia trachomatis

C.

Clamydia pneumoniae

D.


538.

E.

No correct answer

A bird shop owner visits his doctor complaining of a headache, fever, and dry cough that has worsened over the last few days. The patient also complains of a sore throat and muscle aches. A physical exam reveals bilateral rales upon auscultation and mild splenomegaly. The doctor orders a

CXR that reveals a patchy pneumonitis. Diagnosis is confirmed with serological tests. The patient is administered tetracycline and the fever diminishes within 2 days. Which of the following is the most likely cause?

A.

*Chlamydia psittaci

B.

Clamydia trachomatis

C.

Clamydia pneumoniae

D.


E.

No correct answer

539.

A 22-year-old student presents with a nonproductive cough, fever, and sore throat. CXR demonstrates diffuse interstitial infiltrate. Sputum Gram stain shows many PMNs but no organism, and a Giemsa stain reveals intracytoplasmic inclusions in epithelial cells. Doxycycline treatment is begun.

Which of the following is the most likely cause?

A.

Chlamydia psittaci

B.

Clamydia trachomatis

C.

*Clamydia pneumoniae

D.


E.

No correct answer

540.

Which of the following is NOT used for laboratory diagnosis of C. trachomatis?

A.

Microscopy of Gram-negative rods with no peptidoglycan cell wall

B.

Molecular amplification (e.g. PCR)

C.

Cell culture using certain cell lines (e.g. nonciliated columnar, cuboidal)

D.

Antigen test (e.g. ELISA, fluorescence)

E.

*Vaginal specimen cytology

541.


A.

oral cavity

B.

*throat posterior nasopharynx)

C.

nasal membranes

D.


542.

E.

vagina


A.

conjunctiva

B.

*nasopharynx

C.

urogenital tract

D.

blood

E.

meninges

543.

This bacterium, although usually not considered as normal flora, frequently colonizes the stomach and is thought to be the cause of gastric and duodenal ulcers.

A.

Lactobacillus acidophilus

B.


C.

Escherichia coli

D.

Vibrio cholerae

544.

E.


Silver nitrate or an antibiotic is put into the eyes of newborn infants to prevent infection by

A.

Doderlein's bacillus (Lactobacillus acidophilus)

B.


C.


D.

Chlamydia trachcomatis

E.


545.

The fimbriae of enterotoxigenic E. coli are essential to the bacterium when it causes disease because

A.

*they are needed for initial attachment of the bacteria to the gastrointestinal epithelium

B.

they activate host adenylate cyclase enzymes leading to disruption of cellular permeability

C.


D.

they convert GI tract components (bile) to substances which provoke

E.

they allow the bacteria to swim "upstream" against the peristaltic action of the GI tract thereby

546.

remaining established in the GI tract


A.

A. promote colonization of a host

B.


C.


547.

D.

*survive as intracellular parasites !!!!

E.

alter or change their surface antigens within the course of an infection

Leukocidins are

A.


B.


C.


D.


548.

E.

*substances produced by pyogenic bacteria that kill phagocytes


A.

collagenase

B.

streptokinase

C.

streptolysin

D.


549.

E.

*hyaluronidase

A primary determinant of virulence in Streptococcus pyogenes, which is involved in adherence, resistance to phagocytosis and antigenic variation, is

A.

streptokinase

550.

B.

lipopolysaccharide (endotoxin)

C.

*M-protein

D.

Protein A

E.

coagulase

The large volume of fluid lost by diarrhea during infection with Vibrio cholerae

A.


B.


C.


D.



E.


551.

The similarity between the toxic shock syndrome toxin (TSST), the staphylococcal enterotoxins, and the erythrogenic toxin (pyogenic exotoxin) is

A.


B.


C.


D.


E.


552.

Which tissue in a human is free from colonization by microbes (normal flora) because the organisms lack normal access to the tissue?

A.

*blood (vascular system)

B.

colon

C.

stomach

553.

D.

lower respiratory tract

E.

urinary tract (urethra)

Which tissue is normally free from colonization by microorganisms (normal flora) because of the

554.

effectiveness of the host constitutive defenses?

A.

upper respiratory tract (throat, pharynx)

B.

*lower respiratory tract (lungs)

C.

upper gastrointestinal tract

D.

lower gastrointestinal tract

E.

vagina

The predominant bacteria in the mouth, GI tract (colon), and skin, respectively, are

A.

staphylococci, streptococci, and corynebacteria

B.

streptococci, E. coli, and staphylococci

C.

*lactic acid bacteria, Bacteroides, and staphylococci

555.

D.

staphylococci, E. coli, and streptococci

E.

neisseriae, enterococci, and clostridia

The most important benefit that the human gastrointestinal flora provide for their host is

A.

digestion of dietary cellulose

B.

production of endotoxin that produces toxemia

C.

production of dietary protein

D.

*antagonism against colonization by potential pathogens

E.

production of antibodies

The bacterial product that prevents colonization of the vagina by potentially pathogenic yeasts is 556.

A.

bacteriocin

B.

peroxide

C.

TSST toxin

D.

lysozyme

E.

*lactic acid

557.


A.

nasal membranes

B.


558.

C.

oral cavity

D.


E.

vagina

In the pathogenesis of Helicobacter pylori what is the colonization site in the host?

A.

nasal sinuses

B.

*stomach

C.

lower intestine

D.

throat

E.

respiratory tract

559.

560.

What is the colonization site of Corynebacterium diphtheriae, the agent of diphtheria?

A.

skin

B.

urethra

C.

eye

D.

*throat

E.

all are false

A determinant of virulence of Streptococcus pneumoniae which allows the bacteria to resist

561.

engulfment by phagocytes is

A.

fimbriae

B.

*a polysaccharide capsule

C.

production of TSST exotoxin

D.

coagulase

E.

neuraminidase

The fimbriae of pathogenic Neisseria gonorrhoeae are apparently essential to the bacterium when it produces the disease gonorrhea because

A.

*they are responsible for initial attachment of the bacteria to the urethral or cervical epithelium

B.

they cause the production of pus which is characteristic of gonorrhea

C.


D.

D. they convert urinary tract components (urine) to substances which provoke symptoms of disease

E.

E. they allow the bacteria to swim "upstream" against the flow of urine and thereby remain established in the urinary tract

562.

563.

The clostridial invasin that dissolves the framework of muscle is

A.

botulinum toxin

B.

tetanus toxin

C.

*hyaluronic acid

D.

neuraminidase

E.

collagenase

Both the cholera toxin and the E. coli LT toxin

A.


B.

* are identical in their primary structure

C.


D.


E.

all are true

564.

The main effect of E. coli and Vibrio cholerae enterotoxin on host cells of the gastrointestinal tract that leads to the pathology of the diseases, is to

A.


B.


C.


D.


E.


565.

The portion of the bacterial lipopolysaccharide (LPS) that is responsible for the toxicity of the molecule is

A.

*lipid A

B.

lipoteichoic acid

C.

O polysaccharide

D.

Omp A

E.

N-acetylglucosamine (NAG)

566.

The portion of lipopolysaccharide (endotoxin) molecule that is responsible for a bacterium’s antigenic specificity, as well as the existence of multiple serotypes (serovars) among Gram-negative

567.

pathogens, is

A.

lipid A

B.

K antigen

C.

*O polysaccharide

D.

R antigen

E.

H antigen

What bacterial structure or substance is primarily associated with antigenic variation in the

568.

Group A streptococci?

A.


B.

streptokinase

C.


D.

*Polysaccharide

E.

M-protein

A reason not to administer beta lactam antibiotics for a Gram-negative septicemia (blood-borne

569.

infection), unless there is no other alternative, is

A.


B.


C.


D.


E.


Which of the following bacterial toxins behaves as a superantigen through its stimulation of a very large fraction of the host T-cell population?

A.

Streptococcal streptolysin

B.

Salmonella LPS (endotoxin)

C.

Pseudomonas Exotoxin A

D.

*Staphylococcal toxic shock syndrome toxin

E.

E. coli O157 H:7 shiga toxin

570.

571.

Haemolytic uraemic syndrome is caused by:

A.

enteropathogenic Escherichia coli.

B.

enterotoxigenic E. coli.

C.

enteroinvasive

D.

*verotoxigenic E. coli.

E.

enteroaggregative E. coli.

Which of the following bacteria is/are primarily human pathogens?

A.

Salmonella Typhi.

B.

S. Paratyphi A.

C.

S. Paratyphi B.

572.

D.

Shigella

E.

*All are true.

Which of the following media is/are used for blood culture in cases of enteric fever?

A.

*Bile broth.

B.


C.

Selenite-F broth.

D.

Sugar broth.

573.

E.

All are true.

For determining the serotype of infecting organism, detection of which agglutinins is more important in Widal test?

A.

*O.

B.

H.

C.

Fimbrial.

D.

M.

574.

E.

Vi

Bipolar staining is characteristic of:

A.

*Yersinia peslis.

B.

Proteus mirabilis.

C.


D.

Vibrio cholerae

E.

all are true.

Scalded skin syndrome is due to which toxin of Staphylococcus aureus? 575.

A.


B.

Enterotoxin.

C.

Leucocidin.

D.

Haemolysin

E.

Necrotoxin

576.

Isolation of pneumococci from clinical specimens may be attempted by intraperitoneal inoculation

577.

A.

rabbits.

B.

rats.

C.

cell culture.

D.

sheep.

E.

*mice

“Medusa head” appearance of the colonies is characteristic of:

A.

Proteus mirabilis.

B.

Clostridium tetani.

578.

579.

580.

581.

C.

*Bacillus anthracis.

D.


E.

C. botulini

Typical drumstick appearance of bacilli is observed in:

A.


B.

C. tetani.

C.

*С. botulinum.

D.

C. histolyticum.

E.

C. difficilae

Pneumonic plague can be transmitted from man to man by:

A.

droplet infection.

B.

inoculation.

C.

ingestion.

D.

flea bite

E.

*all of the routes.

Which of the following bacteria can cause infective type of food poisoning?

A.

*Salmonella enteritidis.

B.


C.


D.


E.

All are true.

Most important complication/s of enteric fever is/are:

A.

intestinal perforation.

B.

haemorrhage.

C.

circulatory collapse.

D.

* All are true.

E.

All are false

582.

583.

In enteric fever, Salmonella may be isolated from:

A.

urine.

B.

faeces.

C.

blood.

D.

bile

E.

*All are true.

Which of the following serotypes of Salmonella can cause gastroenteritis?

A.

S. Enteritidis.

B.

S. Newport.

C.

S. Typhimurium.

D.

*S. cholerae suis

584.

586.

E.

All are true.


A.

a golden-yellow pigment.

B.

*?-haemolysis on sheep blood agar.

C.


D.


585.

E.

all are true.

Thin, slender and gram-positive bacilli possessing metachromatic granules and showing Chinese letter arrangement are characteristic of:

A.


B.


C.

Bacillus anthracis.

D.


E.



A.

A. immune and non-hypersensitive.

587.

B.


C.


D.


E.

healthy

Cholera toxin resembles which of the following toxins?

A.


B.


C.

Diphtheria toxin.

D.

Tetanus toxin.

E.


588.

589.

590.

591.


A.


B.

Candida spp.

C.


D.

Coliforms.

E.

Rickettsia

Infective-toxic type of food poisoning is caused by:

A.


B.

Salmonella Enteritidis.

C.


D.

Salmonella Dublin.

E.

Yeasts

Which of the following bacteria can grow in alkaline pH?

A.

Lactobacilli.

B.

*Vibrio cholerae.

C.

Salmonella.

D.

Shigella.

E.

Neisseria

The causative agent/s of gas gangrene is/are:

A.


B.

C. novyi.

C.

С. septicum.

D.

C. histolyticum

E.

*all are true.

592.

Dysentery like disease may be caused by

A.

enteropathogenic Escherichia colt.

B.

enterotoxigenic E. coli.

C.

*enteroinvasive E. coli.

D.

verotoxigenic E. coli.

E.

enteroaggregative E. coli.

593.

Which of the following bacteria is negative for fermentation of mannitol?

594.

A.

*Shigella dysenteriae.

B.

S. flexneri.

C.

S. boydii.

D.

S. sonnei.

E.

All are true.

Which of the following specimens is/are most appropriate for culture of bacteria in first week of enteric fever?

A.

*Blood.

B.

Urine.

C.

Faeces.

D.

CSF.

E.

Bile

595.

596.


A.


B.

S. epidermidis.

C.

S. saprophyticus.

D.

S. canis

E.

All are false.

Which of the following bacteria is/are implicated as causative agent/s of non-gonococcal

597.

urethritis?

A.


B.

Ureaplasmau urealyticum.

C.

Mycoplasma hominis.

D.

Herpes virus 2

E.

*All are true.

Which of the following are pyogenic cocci:

A.

A. Streptococcus

B.

Staphylococcus

C.

Pneumococcus

598.

D.

Neisseria

E.

*all of these


A.

other staphylococci

B.

*streptococci

C.

micrococci

D.

enterococci

599.

E.

pneumococci


A.

streptolysin

B.

coagulase

C.

pyrogenic toxin

D.

alpha toxin

E.

leucocidin

600.


A.

Ampicillin

B.

erythromycin

C.

C. methicillin

D.

*amoxycillin

E.

no antibiotic

601.


A.

skin, heart

602.

B.

joints, bone marrow

C.


D.

brain, kidney

E.

heart, bone marrow


A.

*Alpha

603.

604.

B.

Beta

C.

Gamma

D.

Delta

E.

Epsilon


A.


B.


C.

Neisseria. gonorrhoeae

D.

*Streptococcus. pneumoniae

E.

Micrococcus luteus


A.

pneumonia

B.

meningitis

C.


D.

otitis media

E.

arthritis

605.

606.

607.

608.

610.

E.

urethritis


A.

blood clots

B.


C.

erysipelas

D.

exotoxin in skin

609.

E.

E. skin invasion by N. meningitidis


A.


B.


C.


D.


E.


What is the usual habitat of Endopore-forming bacteria that are agents of disease?

A.

the intestine of animals

B.

*soil

C.

water

D.

foods

E.

dust

611.


A.

Branhamella

B.

Staphylococcus

C.

Streptococcus

D.

*Neisseria

E.

Shigella


A.


B.


C.

sugar fermentation

D.

beta-hemolysis

E.

alfa- hemolysis


A.

i*nfertility

B.


C.

arthritis

D.

blindness

Most Bacillus species are

A.

true pathogens

B.

opportunistic pathogens

C.

*nonpathogens

612.

613.

614.

615.

616.

617.

618.

619.

620.

621.

D.

commensals

E.

saprophyticus

Many clostridial diseases require a/an ______ conditions for their development.

A.

*anaerobic

B.

aerobic

C.

living tissue

D.

low-pH

E.

alkaline pH

Clostridium perfringens causes

A.

angine

B.

*enterocolitis, haemorrhagic syndrom

C.

antibiotic-induced colitis

D.

All are true

E.

All are false

An infection peculiar to swine causes when transmitted to humans.

A.

anthrax

B.

diphtheria

C.

*erysipeloid

D.

plage

E.

tuberculosis

Which infectious agent cause pseudomembranous collitis?

A.


B.


C.

Mycobacterium leprae

D.


E.

Shigella sonnei

Which infectious agents cause food poising?

A.

Bacillus anthracis

B.

Clostridium tetani

C.


D.


E.

all of these

A unique characteristic of many isolates of Pseudomonas useful in identification is

A.

drug resistance

B.

fecal odor

C.

*green pigment

D.

gram staining

E.

motility

A classic symptom of pertussis is

A.

labored breathing

B.

convulsions

C.

headache

D.

*paroxysmal coughing

E.

redish of skin

The severe symptoms of pertussis are due to what effect?

A.

irritation of the glottis by the microbe

B.

pneumonia

C.

*damage of function of the respiratory epithelium

D.

blocked airways

E.

E. heart disease

For Escherichia coli most impotent which antigens?

A.

capsular

B.

*somatic

C.

flagellar

D.

Vi

E.

all are true


622.

A.

E. coli

B.

Klebsiella

C.

Proteus

D.

Vibrio

E.

*Shigella

Which of the following represents a major difference between Salmonella and Shigella infections?

A.

incubation period

B.

mode of transmission

C.

*place of location in intestine

D.

presence/absence of fever and diarrhea

E.

the portal of entry

623.

624.

Complications of typhoid fever are:

A.

intestinal perforation

B.

liver abscesses

C.

both a and b

D.

*neurological damage

E.

sepsis

Shigella is transmitted by

A.


B.

flies

C.

both a and b

D.

air dropled

625.

626.

E.

louse

Lyme disease is caused by ______ and spread by ______.

A.

Borrelia recurrentis, lice

B.

*Borrelia burgdorferi, ticks

C.

Borrelia burgdorferi, chiggers

D.

Borrelia hermsii, ticks

E.

Borrelia recurrentis, ticks

Chlamydia trachomatis can attacks which structure(s)?

A.

eye

B.

urethra

C.

fallopian tubes

D.

lungs

E.

*all of these

627.

628.

Ornithosis is a _____ infection associated with ______

A.

rickettsial, parrots

B.

chlamydial, mice

C.

*chlamydial, birds

D.

rickettsial, flies

E.

chlamydial, rats

Mycoplasmas demage next structure of host cells.

A.

nucleus

B.

cell walls

C.

ribosomes

D.

*cell membranes

E.

mitochondria

629.


A.


B.


C.


D.


E.


630.


A.


B.


C.


D.


631.

E.

Nucleic acids


A.


B.


C.


D.


E.


632.


A.


B.

Innate and humoral.

C.


D.


E.


633.

An elderly man develops pneumonia and septicemia. Gram stain of sputum contains many neutrophils and Gram-positive cocci, in pairs. Blood and sputum cultures grow out a Gram-positive coccus, alpha-hemolytic on sheep blood agar, and catalase-negative. Which organism below is most likely?

A.


B.


C.


D.


634.

E.



A.


B.


C.


D.


635.

E.


A stool sample is plated on standard Endo-agar plates. After overnight incubation some of the colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the

636.

bacteria that produced dark-pink colonies?

A.

Gram-positive.

B.

*Ferment lactose.

C.


D.

Non-motile.

E.

Produce capsules.

A 35-year-old woman presents with a history of increasing respiratory distress and cough productive of sputum. Chest X-ray shows evidence of bilateral pneumonia. Cultures of blood and sputum on Chocolate agar grow out slender Gram-negative rods; cultures on standard sheep blood agar are negative. Which bacterium is most likely to be the cause of her infection?

A.

Mycoplasma pneumoniae.

B.


C.

*Haemophilus influenzae.

D.

Escherichia coli.

637.

E.



A.


B.


C.


D.


E.


638.

In the morning mss R. had become ill, with high fever, severe headache, and stiff neck. She was admitted to the hospital. Later that day she developed rash, at first petechial and then pupuric. Gram stain of CSF showed many white cells and Gram-negative cocci, many in pairs. Which organism is most likely to be the cause of her infection?

A.

Escherichia coli.

B.


C.


D.


E.


639.

A patient with septicemia goes into septic shock. Blood cultures later showed the pathogen to be

Escherichia coli. Which component of the bacteria was most likely to have produced shock?

A.


B.

Teichoic acid.

C.


D.


640.

E.



A.


B.


C.


D.


E.


641.

Administration of which of the following vaccines would be contra-indicated in an patient with impaired cell-mediated immunity?

A.

Pneumococcal vaccine (pediatric).

B.

Pneumococcal vaccine (adult).

C.

*BCG vaccine against tuberculosis.

D.

Tetanus toxoid.

E.

Acellular Pertussis vaccine.

642.

A sexually-active woman develops a urinary tract infection which ascends to the kidneys. Blood culture yields a ?-hemolytic Gram-negative rod. In this situation, which pathogen is most common?

A.

*Escherichia coli.

B.


C.


D.

Salmonella enteritidis.

E.

Serratia marcescens.

643.



A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

644.

E.

*Shigella.

A child develops a “cold” which progresses to severe pharyngitis. Pharyngeal exudate forms a tough ‘membrane’, difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which organism is most likely to have caused this infection?

A.


B.


C.

Candida albicans.

D.


E.


645.


A.

Bacillus anthracis.

B.

Bacillus cereus.

C.


D.


E.


646.

Untreated pharyngitis produced by Group A streptococci can result in later development of

647.

Acute rheumatic fever, created by cross-reaction of anti-streptococcal antibodies with heart tissue.

Which streptococcal antigen stimulates formation of these cross-reactive antibodies?

A.

Group A carbohydrate.

B.

Flagella.

C.

*M protein

D.

Peptidoglycan.

E.

Teichoic acid.

A child is diagnosed with Pertussis. How was this infection most likely to have been acquired?

A.

Bite of a dog or cat.

B.

Consumption of dairy products made from unpasteurized milk

C.

Contact with livestock or animal products such as leather or wool.

D.

*Inhalation of respiratory droplets of another human being.

E.

Release of oral flora into the bloodstream by dental work

648.

Infections with Salmonella enterica, serotype typhi, spread throughout the body. A key to the ability of serotype typhi to spread systemically is its ability to multiply intracellularly. Multiplication in which cell type(s) is principally responsible for systemic spread?

A.

*Monocytes/macrophages.

B.

Basophils.

C.

Enterocytes.

D.

Erythrocytes.

649.

E.

Neutrophils.


A.


B.


C.


D.


650.

E.


A vacationer has “Traveler’s diarrhea” produced by enterotoxigenic E. coli. His profuse watery diarrhea is produced by a protein exotoxin secreted by this bacterium. Which statement below best

651.

describes the effect of this exotoxin?

A.

Kills enterocytes and produces ulceration and inflammation.

B.

Paralyzes phagocytosis by neutrophils.

C.

*Stimulates ion transport by enterocytes into the intestinal lumen.

D.

Blocks adsorption of nutrients by enterocytes.

E.

Causes rearrangement of the enterocyte cytoskeleton and disappearance of the brush border.


A.


B.


C.


D.


E.


652.


Streptococcus?

A.


B.

Bile-esculin test.

C.


D.


653.

E.



A.


B.


C.


D.


E.


DNA.

654.

A medical student with a three-week history of respiratory illness is treated with erythromycin [a macrolide]. Which phrase best describes the process inhibited by this drug?

A.

Transcription by bacterial RNA polymerase.

B.

Supercoiling of bacterial DNA.

C.

Cross-linking of peptidoglycan.

D.

Polymerization of peptidoglycan.

E.

*Peptide bond formation by bacterial ribosomes.

655.


A.

M-proteins.

B.


C.


D.


656.

E.



657.

A.


B.

Gall bladder.

C.

Large intestine.

D.

*Nasopharynx.

E.



658.

659.


A.

A membrane-bounded inclusion body, within the nucleus.

B.

*A membrane-bounded inclusion body, within the cytoplasm.

C.


D.


E.


An infant is brought to the emergency room, cyanotic and with poor muscle tone.

Which condition is most likely given these findings?

A.


B.

Diphtheria.

C.

Anthrax.

D.

*Botulism.

E.

Tetanus.

660.

In what way do Haemophilus influenzae, Neisseria meningitidis, and Streptococcus pneumoniae most closely resemble each other?

A.

*Polysaccharide capsules.

B.

Lipopolysaccharide in their outer membranes.

C.

Teichoic acid in their envelopes.

D.

Thick peptidoglycan in their cell walls.

E.

Motility due to flagella.

661.

A patient becomes infected with Salmonella enterica serotype typhi. Which condition would most strongly favor development of a “chronic carrier state” with this organism?

A.

Age over 70 years.

B.

Infection via the respiratory route.

C.

*Gallstones.

D.

Kidney stones.

E.

Chronic pulmonary disease.

662.


A.


B.

*Tissue ischemia.

C.


D.


E.


663.


A.


B.


C.


D.


E.


664.

665.


A.


B.


C.

Escherichia coli.

D.


E.


A 50-year-old woman was treated for cystitis [caused by E. coli] with an oral broad-spectrum antibiotic. Three weeks later she developed abdominal pain and diarrhea. A stained smear of stool contained many neutrophils. Cultures for bacterial pathogens were negative. A serological test of stool for Clostridium difficile toxin was positive. Which of the following is most likely to have been the immediately predisposing cause of this patient’s

F.

difficile infection?

A.


B.


C.


D.


E.

All are true

666.

667.

Chancroid is caused by

A.

Treponema pallidum

B.

*Hemophilus ducreyi

C.

Treponema pallidum

D.

Clostridium sp.

E.

All answers are true


A.


B.


C.


D.


668.

669.

674.


A.


B.


C.

heat stable

D.

heat resistent

E.


670.

671.


A.


B.

hyaluronidase

C.

endotoxin

D.

*enterotoxin

E.

neurotoxin


A.


B.


C.


D.


672.

E.



A.

growth in 6.5% NaCl

B.

*oxidase positive

C.

catalase negative

D.

PYR positive

673.

E.

motility


A.


B.


C.

*motility

D.

citrate utilization

E.


Which of the following descriptions best fits a typical strain of Escherichia coli?

A.

non-motile, aerogenic, lactose fermenting mucoid colony

B.

motile, anaerogenic, non-lactose fermenting, indole positive

C.

*motile, aerogenic, lactose fermenting, indole positive

D.

motile, aerogenic, non-lactose fermenting, citrate negative

E.

non-motile, ferments lactose slowly, gramnegative

675.

E.



A.


B.


C.

Streptococcus bovis

D.


676.

677.

Hemolytic uremic syndrome is caused by which of the following bacterium?

A.


B.

*Escherichia coli 0157

C.

Helicobacter pylori

D.

Salmonella typhi

E.

Ureaplasma

What is the most common cause of urinary tract infections?

A.


B.

Escherichia coli

C.


D.

Streptococcus bovis

E.


Which of the following result(s) best describe(s) the listed organism?

A.

Campylobacter jejuni - gram positive gull wings

B.

Shigella Sonneii – mannitol negative H2S (wk)

C.

*E coli 0157 – lactose positive, indole positive

D.

Yersinia enterocolitica –sporulated, colony sick yellow

E.

Clostridium perfringens – aerobes, sporulated

678.

Which of the following tests may be used to differentiate Salmonella paratyphi from Shigella species?

A.

Fermentation of glucose

B.


C.

gram staining

679.

680.

D.

citrate utilization of Simmons’ citrate agar

E.

shape


A.


B.


C.


D.


E.

motile, anaerogenic, lactose fermenting, sporulated

Syphilis is caused by which of the following?

A.

Helicobacter pylori

B.

Proteus mirabilis

C.

*Treponema pallidum

D.

Serratia marcesans

E.

Treponema Vincentii

681.

Borellia burgdorferi causes which disease?

A.

*Lyme Disease

B.

Rocky Mountain Spotted Fever

C.

Hanta

D.

Rabies

E.

Relapsing fever

682.

683.

How is leptospirosis, caused by Leptospira interrogans, transmitted?

A.

Tick bite

B.

*Contaminated urine in food or water

C.

Undercooked meat

D.

Inhaled aerosol

E.

louse feces

What is the most common human pathogen/opportunist?

A.


B.

Steptococcus pneumoniae

C.


684.

D.

Escherichia coli

E.

Enterococcus

Which of the following is NOT true about Bordetella pertussis?

A.

Causes Whooping Cough

B.

Attaches to ciliated cells with capsules

C.

Complications can include pneumonia, brain damage and death

D.

*Gram negative anaerobe

E.

Form pelicle on liquid (20 % blood broth) nutrient medium

Which of the following is NOT true of Neisseria meningitidis? 685.

A.


B.


C.


D.


E.

Utilize glucose and mannitol

686.

Helicobacter pylori, a cause of peptic ulcers and gastric carcinoma, is diagnosed by which of the following methods?

A.


B.

Biopsy (invasive)

C.

*Radioactive isotope C14 test

D.

Bacteriological

687.

E.

All are true

Which of the following does not occur when an individual is infected with Salmonella enteriditis?

A.

Endotoxins cause inflammation and fever

B.

Enterotoxins cause diarrhea

C.

Cytotoxins lyse endothelial cells lining the intestinal tract

D.

*Proteolytic enzymes cause necrosis

688.

E.

Salmonellosis

What is the primary cause of death from Salmonella typhi (Typhoid fever)?

A.

*Hemorrhaging necrosis

B.

DIC (disseminating intravascular coagulation)

C.

Toxemia

D.

High fever

E.

Vomiting

689.

690.

691.

Which of the following members of the Clostridium family causes pseudomembranous colitis?

A.

Clostridium tetani

B.


C.


D.


E.

Clostridium septicum

Which of the following is NOT a major symptom of Corynebacterium diphtheriae?

A.

Formation of a leathery pseudomembrane

B.

Lesions on tonsils

C.

*Flat, pink rash on abdomen

D.

Inflammation of heart and nervous system

E.

Toxic complication

Which of the following methods is used to help clear an anaerobic infection?

A.

Removal of dead tissue

B.

Drainage of infected area

C.

Oxidizing agents/hyperbaric chambers

D.

Use of antibiotics

692.

E.

*All are true

What causes gas gangrene?

A.


B.

Leptospira interrogans

C.


D.

Escherichia coli

693.

E.

Clostridium tetani

An outbreak of sepsis caused by Staphylococcus aureus has occurred in the newborn nursery.

You are called upon to investigate. According to your knowledge of the normal flora, what is the MOST

694.

likely source of the organism?

A.

Colon

B.

*Nose

C.

Throat

D.

Vagina

E.

All are true


A.


B.


C.


D.


695.

696.

E.

All are true


A.


B.


C.

Escherichia coli

D.

Vibrio cholerae

E.

All are true

Each of the following organisms is an important cause of urinary tract infections EXCEPT:

A.

Escherichia coli

B.

Proteus mirabilis

C.


D.


E.

All are true

697.

Your patient is a 30-year-old woman with nonbloody diarrhea for the past 14 hours. Which one of the following organisms is LEAST likely to cause this illness?

A.


B.


C.


D.


698.

E.

All are true

Each of the following statements concerning Mycobacterium tuberculosis is correct EXCEPT:

A.

After being stained with carbolfuchsin, M. tuberculosis resists decolorization with acid alcohol

B.

M. tuberculosis has a large amount of mycolic acid in its cell wall

C.

*M. tuberculosis appears as a red rod in Gram-stained specimens

D.

M. tuberculosis appears as a red rod in acid-fast stained specimens

E.

All are true

699.

Your patient has subacute bacterial endocarditis caused by a member of the viridans group of streptococci. Which one of the following sites is MOST likely to be the source of the organism?

A.

Skin

B.

Colon

C.

*Oropharynx

D.

Urethra '

E.

All are true

700.

A culture of skin lesions from a patient with pyoderma (impetigo) shows numerous colonies surrounded by a zone of beta hemolysis on a blood agar plate. A Gram-stained smear shows grampositive cocci. If you found the catalase test to be negative, which one of the following organisms would

701.

you MOST probably have isolated?

A.


B.


C.


D.


E.

All are true

The coagulase test, in which the bacteria cause plasma to clot, is used to distinguish

A.


B.


C.


702.

D.

Staphylococcus epidermidis from Neisseria meningitidis

E.

All are true


A.


B.


C.


D.


703.

E.

All are true

Five hours after eating fried rice at a restaurant, a 24-year-old woman and her husband both developed nausea, vomiting, and diarrhea. Which of the following organisms is the MOST likely to be involved?

704.

A.


B.


C.

*Bacillus cereus

D.

Salmonella typhi

E.

All are true

For which one of the following enteric illnesses is a chronic carrier state MOST likely to develop?

A.

Campylobacter enterocolitis

B.

Shigella enterocolitis

C.

Cholera

D.

*Typhoid fever

E.

All are true

705.

706.

Each of the following statements concerning chlamydiae is correct EXCEPT:

A.

Chlamydiae are strict intracellular parasites because they cannot synthesize sufficient ATP

B.

Chlamydiae possess both DNA and RNA and are bounded by a cell wall

C.

trachomatis has multiple serotypes, but C psittaci has only one serotype

D.

*Most chlamydiae are transmitted by arthropods

E.

All are true


A.


B.


C.


D.


707.

E.

All are true

Your patient is a 70-year-old man who underwent bowel surgery for colon cancer 3 days ago. He now has a fever and abdominal pain. You are concerned that he may have peritonitis. Which one of the

708.

following pairs of organisms is MOST likely to be the cause?

A.


B.


C.


D.


E.

All are true

A 65-year-old man develops dysuria and hematuria. A Gram stain of a urine sample shows gram-negative rods. Culture of the urine on EMB agar reveals lactose-negative colonies without evidence of swarming motility. Which one of the following organisms is MOST likely to be the cause of his urinary tract infection?

A.

Enterococcusfaecalis

B.


C.

Proteus vulgaris

D.

Escherichia coli

E.

All are true

709.

A 25-year-old man complains of a urethral discharge. You perform a Gram stain on a specimen of the discharge and see neutrophils but no bacteria. Of the organisms listed, the one MOST likely to

710.

cause the discharge is

A.

Treponema pallidum

B.


C.

Candida albicans

D.

Coxiella burnetii

E.

All are true

Two hours after a delicious Thanksgiving dinner of barley soup, roast turkey, stuffing, sweet potato, green beans, cranberry sauce, and pumpkin pie topped with whipped cream, the Smith family of four experience vomiting and diarrhea. Which one of the following organisms is MOST likely to cause these symptoms?

A.

Shigella flexneri

B.


C.


D.


711.

E.

All are true


A.


B.


C.


D.


712.

E.

All are true

The MOST important way the host circumvents the function of the pneumococcal polysaccharide capsule is via

A.


B.


C.


D.


E.

All are true

713.

The pathogenesis of which one of the following organisms is MOST likely to involve invasion of the intestinal mucosa?

A.

Vibrio cholerae

B.

*Shigella sonnei

C.


D.


E.

All are true

714.

Which one of the following organisms that infects the gastrointestinal tract is the MOST frequent cause of bacteremia?

A.

Shigella flexneri

B.


C.

Vibrio cholerae

715.

716.

D.

*Salmonella typhi

E.

All are true

Each of the following statements concerning Bacteroides fragilis is correct EXCEPT:

A.

fragilis is a gram-negative rod that is part of the normal flora of the colon

B.

*ragilis forms Endopores, which allow it to survive in the soil

C.

The capsule of B. fragilis is an important virulence factor

D.

fragilis infections are characterized by foul-smelling pus

E.

All are true


A.


B.


C.

The majority of clinical isolates of S. aureus elaborate penicillinase; therefore, presump-

D.

tive antibiotic therapy for S. aureus infections should not consist of penicillin G

E.


717.

Each of the following statements concerning gram-negative rods is correct EXCEPT:

A.

*Escherichia coli is part of the normal flora of the colon; therefore, it does not cause diarrhea

B.

coli ferments lactose, whereas the enteric pathogens Shigella and Salmonella do not

C.

Klebsiella pneumoniae, although a cause of pneumonia, is part of the normal flora of the colon

D.

Proteus species are highly motile organisms that are found in the human colon and cause urinary tract infections

E.

All are true

718.



A.


B.


C.

Proteus mirabilis

D.


E.

All are true

719.

The pathogenesis of which one of the following diseases does NOT involve an exotoxin?

A.

Scarlet fever

B.

*Typhoid fever

C.

Toxic shock syndrome

D.

Botulism

E.

All are true

Regarding the effect of benzylpenicillin (penicillin G) on bacteria, which one of the following 720.

organisms is LEAST likely to be resistant?

A.


B.


C.


D.


E.

All are true

721.

Each of the following statements concerning chlamydial genital tract infections is correct

EXCEPT:

A.

*Infection can be diagnosed by finding anti-chlamydial antibody in a serum specimen

B.

Infection can persist after administration of penicillin

C.

Symptomatic infections can be associated with urethral or cervical discharge containing many polymorphonuclear leukocytes

D.

There is no vaccine against these infections

E.

All are true

722.


A.


B.

IgA protease

C.

*M protein

D.

Pili

723.

E.

All are true


A.

*Protein A

B.

M protein

C.

Beta-hemolysin

D.


E.

All are true

724.

Three organisms, Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. cause the vast majority of cases of bacterial meningitis. What is the MOST important

725.

pathogenic component they share?

A.

Protein A

B.

*Capsule

C.

Endotoxin

D.

p-Lactamase

E.

All are true

Each of the following statements concerning Chlamydia trachomatis is correct EXCEPT:

A.

It is an important cause of nongonococcal urethritis

B.

It is the cause of lymphogranuloma venereum

C.

*t is an important cause of subacute bacterial endocarditis

D.

It is an important cause of conjunctivitis

726.

E.

All are true

Which one of the following types of organisms is NOT an obligate intracellular parasite and therefore can replicate on bacteriologic media?

A.

Chlamydia

B.

*Mycoplasma

C.

Adenovirus

D.

Rickettsia

727.

E.

All are true


A.


B.


C.


D.


E.

All are true

728.

The soil is the natural habitat for certain microorganisms of medical importance. Which one of the following is LEAST likely to reside there?

A.

Clostridium tetani

B.

Mycobacterium intracellular

C.

Bacillus anthracis

729.

D.


E.

All are true

Of the organisms listed below, which one is the MOST frequent bacterial cause of pharyngitis?

A.


B.


C.


D.


730.

E.

All are true

Which one of the following organisms causes diarrhea by producing an enterotoxin that activates adenylate cyclase?

A.

*Escherichia coli

B.


C.


D.


731.

E.

All are true


A.


B.


C.


D.


732.

E.

All are true


A.

*Escherichia coli

B.


C.


D.


733.

E.

All are true


A.


B.


C.


D.


E.

All are true

734.

735.


A.


B.


C.


D.


E.

All are true

Resident flora can be found in all of the following locations in the human body EXCEPT the:

A.

eye

B.

skin

C.

*blood

736.

D.

mouth

E.

large intestine

In which of the following anatomical locations would you expect to find the largest microbial population?

737.

738.

A.

mouth

B.

skin

C.

kidneys

D.

*large intestine

E.

upper respiratory tract

Bacteremia is

A.

disease associated with bacterial infections of the cerebrospinal fluid.

B.

disease associated with bacterial infections of the lower respiratory tract.

C.

*disease associated with bacterial infections of the bloodstream.

D.

disease caused by ingestion of a bacterial toxin.

E.

disease caused by Clostridium difficile and Candida albicans in the intestinal tract.


A.


B.


C.


D.

Escherichia coli.

739.

E.

Streptococcus pneumonia

A lactose-fermenting Gram-negative rod is isolated from the bloody stool of a young child.

Which pathogen is most likely?

A.

Salmonella enterica.

B.

*Escherichia coli.

C.

Vibrio cholerae.

D.


740.

E.


A 15-year-old female presented with a three-day history of fever, headache and a non-productive cough. Penicillin was prescribed and the patient was sent home. Her illness did not respond to this antibiotic. Gram stain and culture of the patient's sputum and a throat swab revealed only 'normal oral flora'. She was then successfully treated with erythromycin. Which organism below is most likely to have caused her illness?

A.


B.


C.


D.


741.

E.


Which organism below, if present in only one of three blood cultures from a single patient, is most likely to represent contamination caused by poor antiseptic technique, rather than genuine

742.

infection?

A.

*Staphylococcus epidermidis.

B.


C.

Escherichia coli.

D.


E.


Which of the following bacteria can be successfully cultured on cell-free medium?

A.


B.

Coxiella burnetii.

C.

Mycobacterium leprae.

D.


743.

E.

Rickettsia prowazekii.


A.


B.


C.

Streptococcus mitis

D.


E.


744.

A post-surgical patient develops redness around the incision and a day later pus begins to ooze from the wound. Culture of a swab of pus produces beta-hemolytic colonies on Sheep blood agar. Gram stain shows that the bacteria are Gram-positive cocci. Catalase and coagulase tests are positive. Which of the following organisms is most likely?

A.


B.


C.

Streptococcus mitis

D.


E.


745.

A young woman develops urgency, frequency, and dysuria. Two days later she develops fever, chills, and costovertebral angle tenderness. Tests of urine for leukocyte esterase and nitrate reductase are positive. Urine culture yields a beta-hemolytic Gram-negative rod which forms dark-pink colonies on

746.

MacConkey agar. Which of the following organisms is most likely?

A.


B.

Klebsiellla pneumoniae

C.

*Escherichia coli

D.


E.

Enterobacter, sp.

A vacationer develops watery diarrhea but not chills or fever. In this setting which of the following pathogens is the most common?

A.

Salmonella enterica

B.

*Escherichia coli

C.


D.


E.

Helicobacter pylori

747.

A child develops a "cold" which progresses to severe pharyngitis. Pharyngeal exudate forms a tough 'membrane', difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which

748.

organism below is most likely to have caused this infection?

A.


B.


C.


D.


E.


A burn patient develops infection of the burn wound. Culture of exudate on Brain-Heart Infusion agar produces numerous green-pigmented colonies of a Gram-negative rod. The organism grows well aerobically on standard media but shows no evidence of acid production on differential media such as

MacConkey, Hektoen Enteric, or Triple-Sugar-Iron agars.

749.

What is the most likely organism?

A.


B.

Campylobacter fetus

C.


D.


E.

Escherichia coli

750.

A 19-year-old man comes to your clinic because of thick purulent discharge from the urethral opening of his penis. On Gram-stain of the discharge huge numbers of neutrophils are seen, a few of which contain intracellular Gram-negative cocci. Many of the cocci are in pairs. What is the most likely organism?

A.


B.


C.


D.

Mycoplasma hominis.

E.

Treponema pallidum

751.


A.


B.


C.


D.


E.


752.

Infections with Staphylococcus aureus are on average more severe than infections with other

Staphylococci. What test result distinguishes S. aureus from other members of this genus?

A.

Blackening of a bile-esculin slant.

B.

*Coagulation of citrate-treated plasma.

C.

Beta-hemolysis on sheep blood agar.

D.

Blackening of an oxidase-test disc placed on a colony.

E.

Resistance to bacitracin.

753.


A.


B.


C.


D.

Production of extracellular polysaccharide which allows bacteria to adhere tightly to surfaces.

E.

Formation of spores which are resistant to disinfectants and easily dispersed.

754.

A beta-hemolytic streptococcus is isolated from an infected neonate. Such isolates are often members of Lancefield Group B. The antigenic structure of which bacterial component defines

Lancefield Groups?

A.

Capsule polysaccharide.

B.

*Cell-associated or C-carbohydrate.

C.

Wall and membrane teichoic acids.

D.

Beta-hemolysins.

E.

Filamentous proteins of the cell envelope.

755.


A.


B.


C.


D.


756.

E.


A patient presented with upper back pain. MRI imaging demonstrated inflammation of the T8-

T9 vertebral bodies consistent with osteomyelitis. A bone marrow biopsy, when cultured, produced colonies of Gram-positive cocci.Colonies on Sheep blood agar were 3-4 mm in diameter, off-white and beta-hemolytic. Colonies on Brain-heart infusion (BHI) agar were 2-3 mm in diameter and goldenyellow. Catalase and coagulase tests were positive. What was the most likely pathogen?

A.


B.


C.


D.


E.

Streptococcus mitis

757.

A 20-year-old women presents at a local clinic with fever and abdominal tenderness. She reports having had unprotected sexual intercourse a few weeks earlier. Gram-negative diplococci are seen in a

Gram stain of vaginal secretions; many of the bacteria are inside polymorphonuclear leukocytes. Which virulence factor is most important in aiding this bacterium to initiate infection?

A.


B.

*Adhesive pili.

C.


D.

Endotoxin.

E.

Flagella.

758.

Heavily-encapsulated strains of Neisseria meningitidis are far more virulent than nonencapsulated isolates. How does a capsule enhance virulence?

A.

Binds to the Fc region of some subclasses of human IgG.

B.

Prevents activation of complement by the classical pathway.

C.

Enables bacteria to adhere tightly to mammalian cells.

D.

Reduces access of antibiotics to the bacterial membrane.

E.

*Inhibits phagocytosis by neutrophils

759.

Before the advent of immunization, outbreaks of meningococcal disease were frequent in military camps. A factor in development of such outbreaks is the ability of Neisseria meningitidis to establish an asymptomatic 'carrier state'. What is the predominant site of carriage of meningococci?

A.


B.

Gall bladder.

C.

*Nasopharynx.

D.

Large intestine.

760.

E.

Meninges and choroid plexus.

A 23-year-old medical student had headache and fever one evening. By the next morning she had become very ill, with high fever, severe headache, and stiff neck. She was admitted to the hospital. Later that day she developed rash, first petechial and then pupuric. Her white count was 26,000/ull, with 80% neutrophils and 10% 'bands'. Gram stain ofCSF showed many white cells and numerous bacteria. If the pathogen is Neisseria meningitidis, how would you expect it to appear on Gram stain?

A.

Gram-positive cocci, many in pairs.

B.

Gram-positive cocci, many in clusters.

C.

Isolated Gram-positive cocci.

D.

*Gram-negative cocci, many in pairs.

761.

E.

Gram-negative cocci, many in clusters.

A stool sample is plated on standard MacConkey-agar plates. After overnight incubation some of the colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the

762.

bacteria that produced dark- pink colonies?

A.

Gram-positive.

B.

*Ferment lactose.

C.

Not likely to be 'normal flora'.

D.

Non-motile.

E.

Produce capsules.

A strain of bacteria produced colorless colonies when cultured on standard MacConkey agar. It was then used to inoculate a Sugar-Iron Agar slant. After overnight incubation, the tube was entirely yellow and there were numerous bubbles inside the agar. There is no black precipitate. Which of the following descriptions most accurately describes the metabolic reasons for these observations?

A.

Produces H2S and gas

B.

Ferments lactose and produces gas

C.

*Ferments sucrose and produces gas.

D.

Ferments neither lactose nor sucrose

763.

E.

Ferments glucose only

A vacationing couple both develop severe watery diarrhea which lasts three days. Which organism is the most common etiologic agent of such infections?

A.

Shigella sonnei.

B.


C.

Salmonella typhi.

D.


764.

E.

*Escherichia coli.

Several medical students go to Cancun over spring break. One evening, at a local bar, they drink several pitchers of Margaritas made with crushed ice. They spend the next two days in their hotel room with severe watery diarrhea, but no chills or fever. By the third day they recover completely. Which organism is most likely to have been the cause of their illness?

A.

Non-typhoidal Salmonella.

B.

Helicobacter pylori.

C.


D.

*Enterotoxigenic E. coli.

765.

E.

Non-cholera Vibrio.

A sexually-active woman develops a urinary tract infection which ascends to the kidneys

(pyelonephritis). Blood culture yields a beta-hemolytic Gram-negative rod. In this situation, which

766.

pathogen below is most common?

A.


B.


C.


D.


E.

*Escherichia coli.

23-year-old woman comes to your office because, for 3 days, she has experienced burning with urination, increased frequency of urination, and a continual feeling that she needs to urinate. She does not have vaginal discharge, fever, or flank pain. Rapid 'dipstick' urine tests are consistent with uncomplicated cystitis. Culture of urine on standard media produces a lactose-fermenting Gram-

767.

negative rod. In situations such as this, what is the most likely pathogen?

A.

Enterobacter faecium

B.

*Escherichia coli

C.


D.

Proteus vulgaris

E.


Which phrase best describes typical infections by Campylobacter jejuni?

A.

Non-inflammatory enteritis

B.

*Inflammatory enteritis

C.

Systemic infection

D.

Urinary tract infection

768.

E.

Meningitis


A.


B.


C.


D.

Escherichia coli.

E.


769.


During the procedure a biopsy of the stomach epithelium is obtained.

770.

Which observation would suggest Helicobacter pylori as the cause of illness?

A.


B.


C.


D.


E.


771.

A child has Pertussis. How was this infection most likely to have been acquired?

A.

Release of oral flora into the bloodstream by dental work.

B.


C.

Contact with livestock, or animal products such as leather or wool.

D.


772.

E.

*Inhalation of respiratory droplets from another person.


A.


B.


C.


D.


773.

E.


A 22-year-old develops an abscess in his peritoneum following rupture of his appendix. Gram stain of exudate from his foul-smelling abscess reveals numerous polymorphonuclear leukocytes, Grampositive cocci, Gram-positive rods, and Gram-negative rods. Aerobic culture of the exudate at 37oC on

blood and MacConkey agar yields only Enterococci.Which of the bacteria below is most likely to be the

Gram-negative rods seen in the stained smear?

A.


B.

Proteus mirabilis.

C.


D.


774.

E.


The young man was injuring in car accident. The affected area of the leg is painful, red, and swollen. During the next 12 hours the swelling increases markedly, the skin of the leg becomes discolored, and fluid-filled blisters appear on the skin. Gram stain of fluid aspirated from a blister reveals large Gram-positive rods. Which organism below is most likely to have caused this infection?

A.


B.


C.


D.

Clostridium tetani.

E.


775.

A patient has endocarditis produced by an alpha-hemolytic Streptococcus. This usually reflects spread of normal flora to the bloodstream. From which site is this isolate most likely to have spread?

A.

Anterior nares.

B.

Facial skin.

C.


D.

Distal urethra.

E.

*Oropharynx

776.

A five-day-old child develops high fever and stiff neck. A spinal tap is performed. A Gramstained smear of cerebrospinal fluid reveals many neutrophils and short, thick, Gram-negative rods of uniform length. This microbes can ferment lactose.Which organism below is most likely to have caused

777.

this infection?

A.

*Escherichia coli

B.


C.


D.


E.


A nine years-old child develops high fever and stiff neck. A spinal tap is performed. A Gramstained smear of cerebrospinal fluid reveals many neutrophils and Gram-negative cocci that resemble paired kidney beans within leucocytes. Which organism below is most likely to have caused this infection?

A.

Escherichia coli

B.


C.


D.


E.


778.


A.


B.


C.


779.

D.


E.

Escherichia coli


A.


B.


C.


D.


780.

E.


The laboratory informs you that an isolate of Staphylococcus aureus is ‘methicillin-resistant’.

Which phrase below best describes such isolates?

A.


B.


C.


D.


E.


781.

A young man has a large pus-filled abscess on his upper arm but does not go to a doctor. Several days later he is brought to the Emergency Room with fever, hypotension, and multiple organ failure.

Which of the following is most likely to be responsible?

A.


B.


C.


D.


E.


782.


A.


B.


C.


D.


783.

E.


A patient with Cystic fibrosis develops pneumonia. A Gram-negative rod is cultured from her respiratory tract. On nutrient-poor media it grows well and secretes large amounts of bright green pigment. It produces acid from none of the sugars on which it was tested (including lactose and sucrose). Which organism below is most likely?

A.

Shigella sonnei

B.

Salmonella typhi

C.


D.

Escherichia coli

E.


784.


A.


B.


C.


D.


E.

Sexually-transmitted

785.

A young woman has a urinary tract infection caused by E. coli. By what route are such infections most commonly acquired?

A.

Respiratory route, followed by spread from the anterior nares.

B.

Respiratory route, followed by spread from the oro-pharyngeal region.

C.

*Fecal-oral route, followed by colonization of the intestine and then the perineum.

D.

Intestinal infection, followed by spread of bacteria to the urethra via the bloodstream.

E.

Direct contact route

786.

787.

What is the most common outcome of infection with Helicobacter pylori?

A.

Severe diarrhea

B.

No clinical manifestations

C.

Bacteremia

D.

Hepatitis

E.

*Peptic ulcers or gastric cancer

A 35-year old patient got fever, nausea, vomiting and bloody diarrhea, all of the following bacteria should be considered in the diffrential diagnosis, except one:

A.

Salmonella

B.

ETEC

C.

Shigella

D.

Yersinia

E.

*Campylobacter

788.


789.

A.


B.

Escherichia coli.

C.


D.


E.


A 40-years-old patient has a peptic ulcer. Which organism is most likely to have created this lesion?

A.


B.


C.

Escherichia coli.

D.


E.


790.


A.

Rare hamburger.

B.

Dog or cat.

C.


D.


E.

*Another child.

791.

A 6-year-old boy was brought to the emergency room with a history of bloody diarrhea over the preceding two days. A fecal smear contained numerous red cells and neutrophils. Stool culture on Endo agar produced lactose-negative colonies amid colonies of ‘normal intestinal flora’. Which of the

792.

organisms below is most likely to be the cause of his illness?

A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

A few healthy adult travelers visiting Peru are cautioned against eating uncooked vegetables and unpeeled fruits, and against drinking unbottled water. However, they are already resistant to cholera because of:

A.


B.


C.


D.


E.


793.


Endo agar produced lactose-negative colonies amid colonies of ‘normal intestinal flora’. Which of the

794.

organisms below is most likely to be the cause of his illness?

A.


B.

Balantidium coli.

C.


D.

D.Giardia lamblia.

E.

*Shigella.



A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

795.

E.

*Shigella.


A.

oxidase activity.

797.

B.


C.


D.


E.


796.


A.


B.


C.


D.


E.


A laboratory got a sample from a patient with diarrhoea. Which of the following media is an

798.

enrichment medium for the isolation of Shigella?

A.


B.


C.


D.

Endo medium

E.

*Selenite F broth.

A laboratory got a sample from a patient with diarrhoea. Cholera toxin resembles which of the

799.

following toxins?

A.


B.

Diphtheria toxin.

C.

Tetanus toxin.

D.


E.



800.


A.


B.


C.


D.


E.


A laboratory got a sample from a patient with diarrhoea. Shigella is transmitted by

801.

A.

ticks

B.

direct contact

C.

air dropled

D.

louse

E.


A laboratory got a sample from a patient with diarrhea. The severe diarrhea of cholera is produced by a protein exotoxin that acts on enterocytes. Which statement below best describes the effect of Cholera toxin?

A.


B.


C.


D.


E.


802.

A laboratory got a specimen from a patient with cholera. The following occurs during the course of disease due to Vibrio cholerae infection, except one:

A.

Patients experience nausea, vomiting, abdominal cramping, and diarrhea.

B.

Patients sometimes lose between 10 to 20 liters of fluid/day.

C.

“Rice-water” stool presents

D.

Patients show signs of disease at 8 to 72 hrs after ingestion of contaminated food or water.

E.

*Patients sustain considerable damage to their intestines.

803.

A man, 38 y.o. has gastritis. The pathogenic mechanisms that make Helicobacter pylori the causative agent of gastritis include the following except:

A.

urease production

B.

catalase production

C.

microaerophilism

D.

motility

804.

E.

*invasive abilities


A.


B.


C.


D.


805.

E.


A microbiologist got a specimen from a patient with cholera. To determine to which species of vibrios infectious agent belongs, the microbiologist performs some tests on colonies cultured from stool

806.

samples. These tests include the following EXCEPT:

A.


B.


C.

phagotyping

D.


E.




A.


B.


C.


D.


E.


807.

A motive not to administer beta lactam antibiotics for a Gram-negative septicemia, unless there is no other alternative, is

A.


B.


C.


D.


E.


808.


A.


B.


C.


D.

Vibrio cholerae

809.

E.

*Shigella sonnei


A.


B.

pink colonies

C.

black colonies

D.


810.

E.



A.


B.


C.


D.

Escherichia coli.

E.


811.


A.


B.


C.

All are true

D.


E.


812.


A.

Escherichia coli.

B.


C.


D.


E.


813.


A.

tetracycline

B.

toxoid

C.

vaccine

D.

antiserum injection

E.


A person got cholera. The large volume of fluid lost by diarrhea during infection with Vibrio 814.

cholerae

A.


B.


C.


D.

is caused when the vibrios bind to the intestinal epithelium and physically or mechanically block

815.

the uptake of fluids by the gut epithelial cells

E.



A person got cholera. What is the incubation period for cholerae?

A.

6 to 8 hours

B.

2 to 4 days

C.

1 to 2 weeks

D.

12 to 24 hours

E.

*48 to 72 hours

A stool sample is plated on standard Endo-agar plates. After overnight incubation some of the 816.

colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the bacteria that produced dark-pink colonies?

A.


B.

Non-motile.

C.

Produce capsules

D.

Gram-positive.

E.

*Ferment lactose.

817.

A test of the patient's serum shows reactivity with Helicobacter pylori antigens. Which of the following is true?

A.


B.


C.

All are true

D.


E.


818.

A urease-positive, spiral-shaped gram-negative rod is found in gastric washings from a 29-yearold stressed-out medical student with gastritis. Which of the following is most likely tobe this organism?

A.

Proteus mirabilis

B.


C.

Vibrio cholerae

D.


E.


819.


A.

Rare hamburger.

B.


C.

Dog or cat.

D.


E.

*Another child.

820.


A.

EHEC

B.

EPEC

C.

EAggEC

D.

ETEC

E.

*EIEC

821.

822.


A.


B.


C.


D.


E.



A.

dogs

B.

cats

C.

swine

823.

D.

chickens

E.

*humans


A.


B.


C.

serotherapy

D.

vaccination

824.

E.


A young woman got cholera. To determine to which species the infectious agent belongs, the microbiologist performs some tests on colonies cultured from stool samples. These tests include the

825.

following EXCEPT:

A.


B.


C.


D.


E.


Among the Sunday night patients at the Smithville emergency room were ten young adults suffering from severe diarrhea. All of these individuals would normally characterize themselves as being in good health. All reported eating at a local Dairy fair during the weekend. Of the following bacterial species the least likely to be responsible is

A.

Campylobacter fetus

B.

Shigella flexneri

C.


D.


826.

E.



A.


B.


C.


827.

D.


E.


Both the E. coli LT toxin and the cholera toxin

A.


B.

are identical in their primary structure

C.


D.


E.

*all answers are correct

By which of the following methods Helicobacter pylori, a cause of peptic ulcers and gastric 828.

829.

carcinoma, is diagnosed?

A.


B.

Biopsy (invasive)

C.


D.


E.

*Bacteriological method

During the procedure a biopsy of the stomach epithelium is obtained. Which observation would

830.

suggest Helicobacter pylori as the cause of illness?

A.


B.


C.


D.


E.



A.

Proteus mirabilis

B.


C.

Vibrio cholerae

D.


831.

E.



A.

milk

B.

poultry

C.

chicken

D.

clams

832.

E.

*hamburger



833.


A.


B.


C.


D.


E.


Healthy adult travelers visiting Peru are cautioned against eating uncooked vegetables and

834.

unpeeled fruits, and against drinking unbottled water. However, they are already resistant to cholera because of:

A.


B.


C.


D.


E.



A.


B.

pink colonies

C.

black colonies

D.


E.


835.


A.

Salmonella

B.

Yersinia

C.

ETEC

D.

Shigella

E.

*Campylobacter

836.


A.


B.


C.


D.


E.


837.

are all


A.


B.

fermentative

C.


D.

pathogens

E.


838.

The microbiologist is aware that the gastroenteritis outbreak is associated with the consumption of raw seafood at a local restaurant. She considers it may be due to a number of vibrios EXCEPT:

A.

V. parahaemolyticus

B.

V. alginolyticus

C.

V. vulnificus

D.

V. cholerae non 01

839.

E.

*V. fluvialis


A.


B.


C.


D.


840.

E.


Which following measures does not prevent Vibrio parahaemolyticus infections?

A.

cook seafood for the appropriate time

B.

proper refrigeration

C.

vaccination

D.

never return cooked seafood to the original container

E.

*consume alcohol along with raw seafood

841.

842.

Which microbe produce verotoxin?

A.


B.


C.

S.dysenterie serotype 8

D.

S.dysenterie serotype I0

E.

*Shigella dysenterie serotype I

Which one of the following organisms is MOST likely to involve invasion of the intestinal mucosa?

A.


B.


C.


D.

Vibrio cholerae

E.

*Shigella sonnei

843.

Young woman got cholera. Which of the following is the least accurate statement regarding

Vibrio cholerae?

A.

Cholera toxin is closely related to E. coli LT (heat labile toxin).

B.

Infected patients suffer from electrolyte deficiency and metabolic acidosis.

844.

C.

Fimbrial adhesions produced by the organism facilitate adherence to the brush border of intestinal epithelial cells.

D.

Can grow on alkalaine media

E.



Of the following, which one is the LEAST likely organism to cause this infection?

A.


B.

Vibrio cholerae

C.


D.


E.


845.


846.

847.


A.

E. coli

B.

Klebsiella

C.

Proteus

D.

Vibrio

E.

*Shigella


A.

Beta

B.

Gamma

C.

Delta

D.

Epsilon

E.

*Alpha

The ___________ test is employed in chronic and complicated cases of gonorrhea:

A.

Agglutination test

B.

Precipitation test

C.

Neutralisation test

D.

RIHAT

E.

*Bordeux-Gengou complement-fixation test

848.

849.

_____ are surface appendages that allow a bacterium to stick to a surface.

A.

Cell walls

B.

Flagella

C.

Ribosomes

D.

Mitochondria

E.

*Pili

A characteristic of Streptococcus mutans that allows it to initiate dental plaque and dental caries is:

850.

851.

A.


B.

the ability to utilize sucrose as a source of carbon and energy

C.

the ability to produce a dextran capsule

D.

all are right

E.

*the ability to produce lactic acid


A.


B.

arthritis

C.

blindness

D.

urethritis

E.

*infertility

A condition characterized by the multiplication of bacteria in blood.

A.

bacteremia

852.

853.

854.

855.

856.

857.

B.

bulimia

C.

anemia

D.

septicopiemia

E.

*septicemia

A genus of bacteria that are gram - positive organisms occurring in pairs. Also called

A.

streptococcus.

B.

diplobacilli

C.

streptobacilli

D.

coccus

E.

*diplococcus

A gram-positive cocci that occurs in chains.

A.

staphylococcus

B.

rickettsia

C.

streptobacilli

D.

Neisseria

E.

*streptococci


A.

immune and non-hypersensitive.

B.


C.


D.

healthy

E.


A substance that destroys microorganisms has name

A.

viricide

B.

fungicide

C.

germicide

D.

multicide

E.

*bactericide

A type of bacteria that is spherical or ovoid in form.

A.

bacillus

B.

spirillum

C.

spirochete

D.

vibrio

E.

*coccus

What of the statements about the classification of streptococci is correct EXCEPT:

A.

Pneumococci Streptococcus pneumoniae) are alpha-hemolytic and can be serotyped on the basis of their polysaccharide capsules

B.


C.


D.


858.

E.

All are right

Alpha-haemotoxin-producing streptococci are characterized by the appearance of _______ zones around the colonies:

A.

Red

B.

Brown

C.

Colorless

D.

No correct answer

859.

E.

*Green


A.


B.


C.


D.

Streptococcus epidermidis

E.


860.

861.


A.


B.

sugar fermentation

C.

beta-hemolysis

D.

alfa- hemolysis

E.


Bacitracin sensitivity is used to distinguish

A.

Streptococcus pneumoniae from other alpha-hemolytic streptococci.

B.

Staphylococcus aureus from Staphylococcus epidermidis.

C.

Staphylococcus from Micrococcus.

D.

Group A Streptococcus. from Streptococcus pneumoniae.

E.

*Group A Streptococcus from other beta-hemolytic streptococci.

Beta-haemotoxin-producing streptococci are characterized by the appearance of _______ zones 862.

around the colonies:

A.

Red

B.

Brown

C.

Green

D.

No correct answer

E.

*Colorless

863.

864.

Biochemical properties of Streptococci:

A.

non-proteolytic

B.

do not liquefy gelatin

C.

do not reduce nitrates to nitrites

D.

No correct answer

E.

*All answers are correct

Characteristics of Streptococcus mutans which allow it to initiate dental caries include

A.


B.

the ability to form and grow in a biofilm on the enamel of the tooth

C.

all are right

865.

866.

D.

none of the above

E.

*the ability to produce lactic acid from sucrose, glucose and fructose

Choose faithful composition of yolk salt agar

A.

MPA, sheep , 9 % of sodium chloride

B.

MPA, rabbit red cells, 9 % of sodium chloride

C.

MPA, horse red cells , 9 % of sodium chloride

D.

MPA, glucose, 9 % chloride of sodium

E.

*MPA, yolk, 9 % of sodium chloride

Components of Bordeux – Gengou complement fixation test for diagnosis of gonorrhea:

A.

Isotonic sodium chloride solution, discharges from urethra, gonococcal diagnosticum,

867.

868.

complement, hemolytic system (hemolytic serum and 3 % sheep erythrocytes suspension)

B.

Isotonic sodium chloride solution, patient’s serum, gonococcal diagnosticum, complement, hemolytic system (hemolytic serum)

C.

Isotonic sodium chloride solution, patient’s serum, gonococcal diagnosticum, complement, and

3 % sheep erythrocytes suspension)

D.

Isotonic sodium chloride solution, patient’s serum, complement, hemolytic system (hemolytic serum and 3 % sheep erythrocytes suspension)

E.

*Isotonic sodium chloride solution, patient’s serum, gonococcal diagnosticum, complement, hemolytic system (hemolytic serum and 3 % sheep erythrocytes suspension)

Condition of Meningococci cultivation for diagnosis of epidemic meningitis:

A.

The inoculated culture is incubated at 22 °C and in conditions of elevated CO2 contents

B.

The inoculated culture is incubated at 22 °C and in conditions of elevated O2 contents

C.

The inoculated culture is incubated at 37 °C and in conditions of elevated O2 contents

D.

The inoculated culture is incubated at 37 °C

E.

*The inoculated culture is incubated at 37 °C and in conditions of elevated CO2 contents


A.


B.

Escherichia coli

869.

870.

871.

872.

873.

874.

875.

876.

C.

Vibrio cholerae

D.

Rotavirus

E.


Each of the following statements concerning gonorrhea is correct EXCEPT:

A.

Infection in men is more frequently symptomatic tYan in women

B.

A presumptive diagnosis can be made by finding gram-negative kidney-bean-shaped diplococci within neutrophils in a urethral discharge

C.

Gonococcal conjunctivitis of the newborn rarely occurs in the United States, because silver nitrate or erythromycin is commonly used as prophylaxis

D.

All are right

E.

*The definitive diagnosis can be made by detecting at least a 4-fold rise in antibody to Neisseria gonorrhoeae

Each of the following statements concerning neisseriae is correct EXCEPT:

A.

They are gram-negative diplococci

B.

They produce IgA protease as a virulence factor

C.

They are oxidase-positive

D.

All answers are right

E.

*They grow best under anaerobic conditions


A.


B.


C.


D.

All are right

E.



A.


B.


C.


D.


E.



A.


B.


C.

The majority of clinical isolates of S. aureus elaborate penicillinase; therefore, presumptive antibiotic therapy for S. aureus infections should not consist of penicillin G

D.


E.



A.

Pneumococci Streptococcus pneumoniae) are alpha-hemolytic and can be serotyped on the basis of their polysaccharide capsules

B.


C.


D.

No correct answer

E.


For staining the smear from liquor such method may be used:

A.

Ziehl-Neelsen

B.

Loeffler

C.

Burry

D.

Roux

E.

*Gram

From which site is a-hemolytic Streptococcus isolate most likely to have spread in blood?

A.

Anterior nares.

B.


877.

878.

879.

880.

881.

882.

883.

884.

885.

C.

Distal urethra.

D.

Facial skin.

E.

*Oropharynx.

Gonococci are pathogenic for:

A.

Rabbit

B.

Mice

C.

Sheep

D.

Rat

E.

*Human

Gonococcus is pathogenic for:

A.

Rabbits

B.

Mice

C.

Sheep

D.

Rats

E.

*No correct answer

How does Protein A aid in virulence?

A.

Hydrolyzes secretory IgA.

B.

Binds Factor H, prevents activation of complement.

C.

Extracts iron from plasma proteins.

D.

Promotes tight binding of bacteria to extracellular matrix.

E.

*Binds the Fc region of IgG, decreases opsonization.

How we can distinguish S. aureus from staphylococci epidermidis?

A.


B.


C.


D.


E.


In a bacterium, where are proteins synthesized?

A.

nucleus

B.

peroxisome

C.

nucleoid region

D.

capsule

E.

*ribosomes

In serum broth Meningococci produce:

A.

No visible changes

B.

Sedimentation

C.


D.

There is no correct answer

E.

*Turbidity and a sediment at the bottom of the test tube

Indicate biological properties of Staphylococci:

A.

produce urease

B.

produce catalase

C.

produce phosphatase and hydrogen sulphide

D.

No correct answer

E.


Indicate properties of Group A streptococci

A.

Catalase “–“

B.

Beta-hemolysis

C.

Bacitracin sensitive

D.


E.


What microbes do look like irregular grapelike clusters?

A.

streptobacilli

B.

diplobacilli

C.

coccus

D.

Sarcina

E.

*staphylococcus

886.

887.

888.

889.

890.

891.

892.

893.

894.

895.

Leucocidin, a substance which destroys:

A.

Leucocytes

B.

Haematoblasts of the bone marrow

C.

Nerve cells

D.

No correct answer

E.


Leukocidins are

A.


B.


C.


D.


E.

*substances produced by pyogenic bacteria that kill phagocytes

Meningococci were described by:

A.

Pasteur

B.

Koch

C.

Bilroth

D.

Loeffler

E.

*Weichselbaum


A.

?-haemolysis on sheep blood agar.

B.


C.


D.

all are right.

E.

*a golden-yellow pigment.

Neisseria gonorrhoeae is classified with _____.

A.

proteobacteria

B.

chlamydias

C.

spirochetes

D.

cyanobacteria

E.

*gram-negative bacteria

Neisseria meningitidis is classified with _____.

A.

proteobacteria

B.

chlamydias

C.

spirochetes

D.

cyanobacteria

E.

*gram-negative bacteria

Pathogens that are usually beta-hemolytic include

A.


B.

Streptococcus Group D

C.


D.


E.

all answers are correct

Patient has streptococcal pneumonia. What tested material is used for inoculation?

A.

Pus

B.

Cerebrospinal fluid

C.

Blood

D.

Post-mortem organs

E.

*Sputum


A.

ampicillin

B.

erythromycin

C.

methicillin

D.

amoxycillin

E.

*no antibiotic

Pili increase the virulence in which of the following?

A.

Treponema pallidum

B.


896.

897.

898.

899.

900.

901.

902.

903.

904.

C.

Clostridium welchii

D.


E.

*Neisseria gonorrhea


A.

skin, heart

B.

joints, bone marrow

C.

brain, kidney

D.

heart, bone marrow

E.


Rheumatic Fever has such etiology:

A.

Neisserial

B.

Staphylococcal

C.

Moraxella

D.

Peptostreptococcal

E.

*Streptococcal

Scalded skin syndrome is due to which toxin of Staphylococcus aureus?

A.

Enterotoxin.

B.

Leucocidin.

C.

Haemolysin

D.

Necrotoxin

E.


Scarlet fever has such etiology:

A.

Neisserial

B.

Staphylococcal

C.

Moraxella

D.

Peptostreptococcal

E.

*Streptococcal

Sensitivity to bacitracin would best be determined by growing the test organism on

A.

eosin methylene blue agar.

B.

carbohydrate fermentation broth.

C.

MacConkey agar.

D.

All media would be equally suitable.

E.

*blood agar.

Show biological properties of Staphylococci:

A.

liquefy gelatin

B.

coagulate milk and occasionally serum

C.

reduce nitrates to nitrites

D.

No correct answer

E.


Show enzyme with destructive properties

A.

Hyaluronidasa

B.

Phosphatasa

C.

Lecithinase

D.

No correct answer

E.


Show fermentative properties of Meningococci:

A.

do not liquefy gelatin

B.

cause no change in milk

C.

ferment glucose with acid formation

D.

ferment maltose with acid formation

E.

*ferment glucose and maltose with acid formation

Specimens for microscopic examination in patients with gonorrhoeae:

A.

discharge of the urethra,

B.

discharge of the vagina,

C.

discharge of the vulva

D.


E.


905.

906.

907.

908.

909.

910.

911.

912.

913.

914.

Staphylococcus aureus is classified with _____.

A.

proteobacteria

B.

chlamydias

C.

spirochetes

D.

cyanobacteria

E.

*gram-positive bacteria

Staphylococcus aureus, a major pathogen, is usually

A.

alpha hemolytic.

B.

gamma hemolytic.

C.

delta hemolytic.

D.

incapable of hemolysis.

E.

*beta hemolytic.

Staphylococcus grows on/in the ______________ of warm-blooded animals

A.

teeth

B.

large intestines

C.

No correct answer

D.


E.

*skin and mucus membranes

Streptococcus pyogenes is classified with _____.

A.

proteobacteria

B.

chlamydias

C.

spirochetes

D.

cyanobacteria

E.

*gram-positive bacteria


A.

conjunctiva

B.

urogenital tract

C.

blood

D.

meninges

E.

*nasopharynx

The causative agent of gonorrhea is

A.


B.

Treponema pallidum

C.

gonorrhea mycobacterium

D.


E.

*Neisseria gonorrhea

The causative agent of otitis media

A.

Streptococcus pneumoniae (pneumococcus)

B.


C.


D.


E.


The causative agent of rheumatic fever

A.


B.


C.


D.


E.


The causative agent of toxic shock syndrome

A.

Neisseria gonorrhea

B.

Salmonella typhi

C.

Treponema pallidum

D.


E.



A.

other staphylococci

B.

micrococci

C.

enterococci

D.

pneumococci

E.

*streptococci

The coagulase test, in which the bacteria cause plasma to clot, is used to distinguish 915.

A.


B.


C.

Staphylococcus epidermidis from Neisseria meningitides

D.

All are right

E.


916.

The Gonococci do not grow on common media. They grow readily at pH 7.2-7.4 on media to which _________ has been added.

A.

Glucose

B.

Bile

C.

Urine

D.

No correct answer

E.

*Serum

917.

The gonococcus possesses low biochemical activity and no proteolytic activity. It ferments only

_____________ with acid formation

A.

Maltose

B.

Mannitol

C.

Saccharose

D.


E.

*Glucose

918.

The Kirby-Bauer test is used to determine

A.

which carbohydrates a bacteria can ferment.

B.

if the bacteria can produce gelatinase.

C.

if the organism can produce catalase.

919.

D.

the type of hemolysis a bacteria is capable of producing.

E.

*which antibiotics a bacterium is susceptible to.



A.


B.


C.


D.


E.


920.


A.

oral cavity

B.

nasal membranes

C.


D.

vagina

E.


921.


A.

nasal membranes

B.

oral cavity

C.


D.

vagina

E.


922.

The meningococcus is an aerobe or facultative anaerobe and does not grow on common media. It grows readily at pH 7.2-7.4 on media to which _________ has been added.

A.

Glucose

B.

Bile

C.

Urine

D.

No correct answer

E.

*Serum

923.


A.


B.


C.


D.

All are right

E.


924.

The MOST important way the host circumvents the function of the pneumococcal polysaccharide capsule is via

A.


B.


C.


D.

All are right

E.


925.

The most severe streptococcal diseases are caused by

A.

group B streptococci

B.

group C streptococci

C.

pneumococci

D.

enterococci

E.

*group A streptococci

926.

The Neisseria gonorrhoeae does not grow on common media. It grows readily on media to which

_________ has been added.

A.

Glucose

B.

Mannitol

C.

Bile

D.

Yolk

E.

*Ascitic fluid

927.

928.

929.

The organism that produced the plasmocoagulase is most likely

A.


B.


C.


D.

Streptococcus mitis.

E.


The presence of viable bacteria in the blood stream:

A.

serum poisoning

B.

antisepsis

C.

mixed infection

D.

anemia

E.

*bacteremia

The similarity between the toxic shock syndrome toxin (TSST), the staph enterotoxins, and the

930.

erythrogenic toxin (pyogenic exotoxin) is

A.


B.


C.


D.


E.



A.

blood clots

B.

erysipelas

C.

exotoxin in skin

D.

E.skin invasion by N. meningitidis

931.

E.



A.

collagenase

B.

streptokinase

C.

streptolysin

D.


932.

934.

E.

*hyaluronidase


A.

streptolysin

B.

coagulase

C.

alpha toxin

D.

leucocidin

933.

E.

*pyrogenic toxin


A.


B.


C.


D.

All are right

E.


Under anaerobic conditions pathogenic staphylococci break _________to acid:

A.

blood

935.

B.

yolk

C.

urine

D.

tregalose

E.

*mannitol


A.

pneumonia

B.

meningitis

C.

otitis media

D.

arthritis

E.


936.

937.

What are features of Pneumococci?

A.

Their cells are arranged in pairs

B.

Their cells are elongated, resembling a candle flame

C.

Their cells and are surrounded with a capsule

D.


E.


What bacterial structure or substance is primarily associated with antigenic variation in the

Group A streptococci?

A.


B.

streptokinase

C.


D.

M-protein

E.

*Polysaccharide

938.

939.


A.


B.

heat stable

C.

heat resistent

D.


E.


What do we use for specific prophylaxis of meningococcal infection?

A.

Antibiotics

B.

Sulfonamides

C.

Toxoid

D.

Immunoglobulin

940.

E.

*Vaccine

What drug is used for specific prophylaxis of staphylococcal infection?

A.

antitoxic serum

B.

antibiotics

C.

sulphonamides

D.

No correct answer

E.

*staphylococcal toxoid

941.

What drug is used for specific treatment of staphylococcal infection?

A.

staphylococcal anatoxin

B.

antibiotics

C.

sulphonamides

D.

No correct answer

E.

*antitoxic serum

942.

What enzyme does possess destructive properties?

A.

Coagulase

B.

Fibrinolysin

C.

Lecithinase

D.

No correct answer

E.


943.

944.

945.

E.

*C

What is optimal ph for staphylococci?

A.

3.2-3.4

B.

4.2-4.4

C.

5.2-5.4

D.

6.2-6.4

E.

*7.2-7.4

What is the G+C content in DNA 946.

A.

20.0-32.0

B.

40.5-51.0

C.

52.0-61.4

D.

63/0-70.0

E.

*30.7-39.0

947.

What is the most common cause of urinary tract inf::What is the most common cause of urinary tract infections?

A.


B.

Escherichia coli

C.

Streptococcus bovis

D.


E.


948.

What erythrocytes are the most sensitive to the staphylococcal haemotoxin?

A.

pig’s, cat’s

B.

chicken’s, duck’s

C.

all are correct

D.

No correct answer

E.

*rabbit’s, sheep’s

What group-specific polysaccharide do Streptococci produce?

A.

A

B.

B

C.

D

D.

E

949.

What is the optimal temperature for Streptococci growth?

A.

17 1C

B.

27 2C

C.

47 4C

D.

57 5C

E.

*37 3C*

What name is given to the rigid structure, found outside the plasma membrane that surrounds and supports the bacterial cell?

A.

capsule

B.

pili

C.

flagella

D.

nucleoid region

E.

*cell wall

950.

What nucleoprotein substance do Streptococci produce?

951.

952.

953.

954.

955.

956.

957.

958.

959.

A.

A

B.

C

C.

N

D.

O

E.

*P

What nutrient medium is used for inoculation of blood in patient with bacteremia?

A.

Glucouse agar

B.

Yolk salt agar

C.

Yolk salt broth

D.

1 % alkaline peptone water

E.

*Glucose broth

What nutrient medium is used for inoculation of blood for diagnosis of Streptococcal sepsis?

A.

Yolk salt agar

B.

Yolk salt broth

C.

1 % alkaline peptone water

D.

Glucouse agar

E.

*Glucose broth

What nutrient medium is used for inoculation of blood for diagnosis of Pneumococcal sepsis?

A.

Endo’s medium

B.

Yolk salt broth

C.

Blood broth

D.

Glucose agar

E.

*Serum broth

What nutrient medium may be used for primary isolation of staphylococci from tested material?

A.

Endo’s medium

B.

Levin’s medium

C.

Loeffler’s medium

D.

Koch’s medium

E.

*Blood agar

What nutrient medium may be used for primary isolation of staphylococci from tested material?

A.

Loeffler’s medium

B.

Koch’s medium

C.

Ploskirev’s medium

D.

TCBS

E.

*Yolk salt agar

What pigment do staphylococci produce?

A.

Golden

B.

White

C.

Lemon-yellow

D.

No correct answer

E.


What plasma is used for detection of plasmocoagulase activity?

A.

citrated horse plasma

B.

citrated human plasma

C.

citrated chicken plasma

D.

No correct answer

E.

*citrated rabbit plasma

What streptolysins do Streptococci produce?

A.

A and B-streptolysin

B.

P and S-streptolysin

C.

M- and N-streptolysin

D.

W- and S-streptolysin

E.

S-streptolysin

What type of haemolysin do staphylococci produce?

A.

A-

B.

B-

C.

C-

D.

D-

E.


960.

What type-specific protein do Streptococci produce::What type-specific protein do Streptococci produce?

A.

R- and T-substances

B.

P- and T-substances

C.

and T-substances

D.

P- and A-substances

E.

*M- and T-substances

961.

962.

963.

964.

E.

*Neisseria


A.


B.


C.


D.


965.

966.

E.



A.


B.

Candida spp.

C.

Coliforms.

D.

Rickettsia

E.


Which of the following are pyogenic cocci:

A.

Streptococcus

B.

Staphylococcus

C.

Pneumococcus

D.

Neisseria

E.

*all of these

967.

Where is a bacterial cell's DNA found?

A.

ribosomes

B.

nucleus

C.

peroxisome

D.

capsule

E.

*nucleoid region

Which bacterial invasin is mismatched with its activity in the host?

A.

staphylokinase: degrades fibrin

B.

coagulase: clots fibrin

C.

streptolysin: lyses neutrophil membranes

D.

none of the above

E.

*hyaluronidase: degrades the ground substance of connective tissue


A.

Branhamella

B.

Staphylococcus

C.

Streptococcus

D.

Shigella

968.


A.

S. epidermidis.

B.

S. saprophyticus.

C.

S. canis

D.

all are false.

E.



A.


B.


C.


D.


969.

970.

971.

972.

973.

974.

975.

976.

977.

978.

E.


Which of the following causes epidemic meningitis?

A.


B.


C.


D.

Moraxella catarrhalis

E.


Which of the following is a normal skin resident?

A.


B.

Thermoactinomyces vulgaris

C.


D.

Streptococcus cremosis

E.

*Staphylococcus epidermidis


A.


B.

Streptococcus bovis

C.


D.


E.


Which of the following is associated with dental caries?

A.


B.

Lactococcus lactis

C.


D.

Moraxella catarrhalis

E.

*Streptococcus mutans

Which of the following is NOT true of Neisseria gonorrhea?

A.

Is a mucosal pathogen

B.

Can disseminate in the immunosuppressed

C.

Complications include ectopic pregnancy, PID and sterility

D.

Gram-negative diplococci

E.

*Requires a vaginal pH of 5 or more to grow

Which of the following is NOT true of Neisseria meningitidis?

A.


B.


C.


D.

Has peptidoglycan

E.


Which of the following organisms may lead to pseudomembrane formation in the throat?

A.

Corynebaclerium diphtheriae

B.

Treponema Vinsentii

C.


D.

Candida albicans.

E.

*All are correct

Which of the following statements about gonorrhea is true?

A.

Men are frequently asymptomatic carriers.

B.

Bacteremia is common.

C.

Serologic diagnosis is more reliable than culture.

D.

Penicillins are no longer recommended for treatment.

E.

*Gonococci are within leucocytes in a sample


A.


B.


C.


D.


E.



A.


979.

B.

Escherichia coli

C.

Vibrio cholerae

D.

All are right

E.



A.


B.


C.


D.

All are correct

980.

E.



A.


B.

IgA protease

C.

Pili

D.

All are right

981.

E.

*M protein


A.

M protein

B.

Beta-hemolysin

C.


D.

All are right

E.

*Protein A

982.

Which organism below is most likely?

A.


B.


C.


D.


E.


983.

Which statement below most accurately describes the role of M protein in virulence of Group A

Streptococci [Streptococcus pyogenes]?

984.

985.

986.

987.

A.

Shows no antigenic variation, so is not a target for antibodies.

B.

Is a ‘superantigen toxin’ which stimulates Th cells.

C.

Binds Fc regions of Immunoglobulin G molecules.

D.

Inhibit phagocytosis

E.

*Stimulates synthesis of antibodies that cross-reacts with heart tissue.


A.


B.


C.


D.


E.



A.

growth in 6.5% NaCl

B.

catalase negative

C.

PYR positive

D.

motility

E.

*oxidase positive


A.


B.

hyaluronidase

C.

endotoxin

D.

neurotoxin

E.

*enterotoxin

Who did discover gonococci first?

A.

Pasteur

B.

Koch

C.

Weichselbaum

D.

Loeffler

E.

*Neisser

Who did discover Staphylococci? 988.

A.

Pasteur

B.

Ivanovsky

C.

Loeffler

D.

Mueller

E.

*Koch

989.

990.

Who did discover streptococci first?

A.

Pasteur

B.

Koch

C.

*Billroth

D.

Loeffler

E.

Rosenbach

Who did study Staphylococci in details?

A.

Pasteur

B.

Koch

C.

Ivanovsky

D.

Rosenbach

E.

*Loeffler

991.

23-year-old woman comes to your office because, for 3 days, she has experienced burning with urination, increased frequency of urination, and a continual feeling that she needs to urinate. She does not have vaginal discharge, fever, or flank pain. Rapid 'dipstick' urine tests are consistent with uncomplicated cystitis. Culture of urine on standard media produces a lactose-fermenting Gramnegative rod. In situations such as this, what is the most likely pathogen?

A.


B.


C.

Proteus vulgaris

D.


E.

*Escherichia coli

992.

A 20-year-old college student goes to the student health center because of dysuna, frequency, and urgency on urination for 24 hours. She has recently become sexually active. On urmalysis, many polymorphonuclear cells are seen. The most likely organism responsible for these symptoms and signs is

A.


B.


C.

Gardnerella vaginalis

D.

Lactobacillus species

993.

E.

*Escherichia coli

A 23-year-old woman has a history of recurrent urinary tract infections, including at least one episode of pyelonephritis. Blood typing shows the P blood group antigen. Which of the following is likely to be the primary cause of her infections7

A.

Escherichia coli that produce heat-stable toxin

B.

Escherichia coli with K1 (capsular type 1) antigen

C.

Escherichia coli O139 (lipopolysaccharide O antigen 139)

D.

Escherichia coli O157 H7 (lipopolysaccharide O antigen 157, flagellar antigen

E.

*Escherichia coli with P-pili (fimbriae)

994.

A 27 year-old woman is admitted to the hospital because of fever, with increasing anorexia, headache, weakness, and altered mental status of 2 days'duration. She works for an airline as a cabin attendant, flying between the Indian subconti nent and other places in Southeast Asia and the West

Coast of the USA. Ten days prior to admission she had a diarrheal illness that lasted for about 36 hours.

She has been constipated forthe last 3 days. Her temperature is 39 °C, heart rate 68/min, blood pressure

120/80 mm Hg, and respirations 18/mm. She knows who she is and where she is but does not know the date. She is picking at the bed clothes. Rose spots are seen on the trunk. The remainder of the physical examination is normal. Blood cultures are done and an intravenous line is placed. The most likely cause of her illness is

A.

Enterotoxigenic Escherichia coli (ETEC)

B.

Shigella sonnei

C.

Salmonella enterica subspecies enterica serotype Typhimunum (Salmonella Typhimurium)

D.

Enteroinvasive Escherichia coli (EIEC)

E.

*Salmonella enterica subspecies enterica serotypeTyphi (SalmonellfaTyphi)

A 60-year old man was admitted to the hospital 2 weeks previously because of head trauma and 995.

other injuries that resulted from an automobile accident. A urinary tract catheter was inserted at admission and remains in place. The man develops a urinary tract infection with a gram negative bacillus. The probable cause of this patients infection is

A.


B.

Providenaa rettgeri

C.

Escherichia coli

D.

Morganella morgana

E.

*Indeterminable without culture and identification testing

996.

A common serotype of enterohemorrhagic E. coli is ::A common serotype of enterohemorrhagic

E. coli is O157:H7. To which bacterial structure does the "H7" correspond?

A.

Pili.

B.

Capsule.

C.

LPS core polysaccharide.

D.

Porins.

E.

*Flagella.

997.

A five-day-old child develops high fever and stiff neck. A spinal tap is performed. A Gramstained smear of cerebrospinal fluid reveals many neutrophils and short, thick, Gram-negative rods of uniform length. This microbes can ferment lactose.Which organism below is most likely to have caused this infection?

A.


B.


C.


D.


998.

E.

*Escherichia coli

A lactose-fermenting Gram-negative rod is isolated from the bloody stool of a young child.

Which pathogen is most likely?

A.

Salmonella enterica.

B.

Vibrio cholerae.

C.


D.


E.

*Escherichia coli.

999.


A.

Age over 70 years.

B.


C.

Kidney stones.

D.


E.

*Gallstones.

1000.



A.


B.

Teichoic acid.

C.


D.


E.


1001.


A.


B.


C.


D.


E.


1002.

A seven-day-old child develops high fever and stiff neck. A spinal tap is performed. A Gramstained smear of cerebrospinal fluid reveals many neutrophils and short, thick, Gram-negative rods of uniform length. This microbes can ferment lactose.Which organism below is most likely to have caused this infection?

A.


B.


C.


D.


E.

*Escherichia coli

1003.


A.


B.


C.


D.

Serratia marcescens

E.

*Escherichia coli.

1004.

A specimen of thick, bloody sputum from a hospitalized 80-year-old patient with chronic obstructive pulmonary disease is sent for laboratory analyses. The tests yield heavy growth of a lactosepositive, nonmotile, gram-negative rod with a large gelatinous capsule. Which of the following is this bacterium most likely to be?

B.

coli

A.

Enterobacter aerogenes

B.

P. aeroginosa

C.

Y. pseudotuberoulosis

D.

*K. pneumoniae

1005.

A stool sample is plated on standard Endo -agar plates. After overnight incubation some of the colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the bacteria that produced dark-pink colonies?

A.

Gram-positive.

B.


C.

Non-motile.

D.

Produce capsules

E.

*Ferment lactose.

1006.


A.


B.

*Ferments lactose and produces gas

C.

Ferments sucrose and produces gas.

D.


E.


1007.


A.

Salmonella enterica

B.


C.


D.

Helicobacter pylori

E.

*Escherichia coli

1008.

A vacationer has “Traveler’s diarrhea” produced by enterotoxigenic E. coli. His profuse watery diarrhea is produced by a protein exotoxin secreted by this bacterium. Which statement below best describes the effect of this exotoxin?

A.


B.


C.


D.


E.


1009.


A.

Shigella sonnei.

B.


C.

Salmonella typhi.

D.


E.

*Escherichia coli.

1010.



A.


B.


C.


D.

Enterobacter, sp

E.

*Escherichia coli

1011.


A.


B.


C.


D.


E.


1012.


A.


B.


C.


D.


E.


1013.

After inoculation of Escherichia coli on Ploskirev medium the growth of bacteria is inhibited.

What chemical does predetermine this phenomenon?

A.

oxalic acid

B.

sodium sulphite

C.

Bismuth salts

D.

fuchsin

E.

*brilliant green

1014.

After inoculation of faces of the patient Escherichia coli on Ploskirev medium the growth of bacteria is inhibited. What chemical does predetermine this phenomenon?

A.

oxalic acid

B.

sodium sulphite

C.

Bismuth salts

D.

Fuchsin

E.

brilliant green

1015.

After inoculation of the patient’s faces on Endo medium there were grown to types of colonies: one – red with metallic hue, other - colorless. To what group of nutrient media does Endo medium belong to?

A.

Elective

B.

Enriching media

C.

Universal

D.

Selective

E.

Differential diagnostic

1016.

After inoculation of the patient’s faces on Endo medium there were grown to types of colonies: one red with metallic hue, other - colorless. To what group of nutrient media does Endo medium belong to?

A.

Elective

B.

Enriching media

C.

Universal

D.

Selective

E.

*Differential diagnostic

1017.

What changes will seen in Olkenitsky medium when Salmonella typhi was inoculated in it?

A.

To fix the hydrogen sulphide production in this medium is impossible

B.

appearance of greenish precipitate in the column of agar

C.

appearance of bright red precipitate in the column of agar

D.

all medium will be black

E.

*appearance of black precipitate in the column of agar

1018.

An old man has a urinary tract infection caused by E. coli. By what route are such infections most commonly acquired?

A.


B.


C.


D.

coli spreads from skin

E.


1019.

An uncommon serotype of Salmonella enterica subspecies enterica was found by laboratories in the health departments of adjacent states. The isolates were all from a small geographic area on either side of the border between the states, suggesting a common source for the isolates (All the isolates were from otherwise healthy young adults who smoked marijuana the same salmo nella was isolated from a specimen of the marijuana). By what method did the laboratories determine that these isolates were the same?

A.

Capsular (K antigen) typing

B.

DNA sequencing

C.

Sugar fermentation pattern determination

D.

Decarboxylase reaction pattern determination

E.

*O antigen and H antigen typing

1020.

Bacteriologists (using the Kauffman-White classifi::Bacteriologists (using the Kauffman-White classification) made conclusion that outbreak has been caused by Salmonella enterica, serotype

Anatum. Structure of which pair of antigens determined the serotype as Anatum?

A.

Heat-labile and heat-stable enterotoxins.

B.

Peptidoglycan and teichoic acid.

C.

Pili and capsular polysaccharide.

D.

Hemolysin and cell-wall-associated carbohydrate.

E.

*Flagella and O-antigen.

1021.

Blood cultures from the patient in Question 2 grow a non lactose fermenting gram negative bacillus. Which of the following is likely to be a constituent of this organism?

A.

antigen 157, H antigen 7 (0157 H7)

B.

antigen 139(0139)

C.

Urease

D.

K1 (capsular type l)

E.

*Vi antigen (capsule, virulence antigen)

1022.

During a vacation at a Caribbean resort, a 26-year-old executive develops profuse watery diarrhea. If his illness is produced by E. coli, which virulence factor of this organism is most likely to be responsible for the diarrhea?

A.

A conjugative plasmid that contains antibiotic-resistance transposons.

B.

A pathogenicity island which enables E. coli to invade mammalian cells.

C.

An iron-transport system more efficient than that present in non-pathogenic E. coli.

D.

A toxin that cleaves ribosomal RNA's.

E.

*A plasmid-borne gene which encodes a heat-stable peptide toxin that stimulates guanyl cyclase.

1023.

Epidemiologists (using the Kauffman-White classification) report that an outbreak has been caused by Salmonella enterica, serotype Newport. Structure of which pair of antigens determined the serotype as Newport?

A.


B.


C.


D.

Hemolysin and cell-wall-associated carbohydrate

E.


1024.

Escherichia coli and Neisseria meningitidis isolated from blood cultures often have transport systems (for acquiring metal ions from the environment) lacking in their less-virulent relatives. Which metal is acquired by the majority of these systems?

A.

Copper

B.

Sodium

C.

Potassium

D.

Magnesium

E.

*Iron

1025.

Escherichia coli was inoculated in Ressel’s medium. What changes will be observed in nutrient medium, which verify utilization of glucose and lactose?

A.

Changes of the color from a pinky to dark blue in the column of agar

B.

Changes of the color from pinky to dark blue of the slant surface of agar

C.

Changes of the color from a pinky to red of the slant surface of agar

D.

Changes of the color from a pinky to red of the column of agar

E.

*Changes of the color from a pinky to dark blue in the column of agar and slant surface of agar

1026.

For verifying the peptolytic properties of bacteria what substances are examined in nutrient medium?

A.

carbon acid and water

B.

glucose and lactose

C.

carbon acid and nitrogen

D.

mannitol and methanol

E.

indole and hydrogen sulphide

1027.

In Olkenitsky’s medium Escherichia coli was inoculated. What changes will be observed in a medium, which will confirm utilization of glucose and lactose?

A.

The changes of the color from a pinky to yellow in the column of agar

B.

The changes of the color from a pinky to yellow of slant surface of agar

C.

The changes of the color from a pinky to red of slant surface of agar

D.

The changes of the color from a pinky to red of the column of agar

E.

*The changes of the color from a pinky to yellow of the column of agar and slant surface of agar

1028.

Olkenitsky’s medium microorganism which products an urea was inoculated. What changes here will be observed in a medium?

A.

appearance of red precipitate in the column of agar

B.


C.

to fix the urease production in this medium is impossible

D.

appearance of brightly-violet precipitate in the column of agar

E.

*all will become red

1029.

In Olkenitsky’s medium Salmonella typhi, which decomposes glucose to acid was inoculated.

What changes will be observed in a medium, which certify utilization of glucose?

A.

The changes of the color from a pinky to yellow the slant surface of agar

B.

The changes of the color from a pinky to red the slant surface of agar

C.

The changes of the color from a pinky to yellow of the column of agar and the slant surface of agar

D.

The changes of the color from a pinky to red of the column of agar

E.

*The changes of the color from a pinky to yellow of the column of agar

1030.

In Olkenitsky’s medium Salmonella typhi, which forms the hydrogen supplied was inoculated.

What changes will be in a medium in this case?

A.

To fix the hydrogen sulphide production in this medium is impossible

B.


C.

appearance of bright red precipitate in the column of agar

D.

all medium will be black

E.

*appearance of black precipitate in the column of agar

1031.


A.

Basophils.

B.

Enterocytes.

C.

Erythrocytes.

D.

Neutrophils

E.


1032.

It is necessary to check the quality of antibacterial filters. What microorganism is it possible to choose as a test-object?

A.

Salmonella schottmuelleri

B.


C.


D.

Mycobacterium kansassii

E.


1033.

It is necessary to make biochemical identification and examine saccharolytic properties of bacteria. What media could you offer?

A.

Veynberg medium

B.

Zeissler medium

C.

Kitt-Tarozzi medium

D.

Milk

E.

*Hiss media

1034.

It is necessary to study ability of microbes to utilize glucose, saccharose, lactose, production of hydrogen sulphide and utilization of urea. What nutrient media will you recommend?

A.

Ru medium

B.

Leffler medium

C.

Endo medium

D.

Ploskirev medium

E.

*Olkenitsky medium

1035.

Many isolates of E. coli are now ampicillin-resistant because they produce ?-lactamases. Which sentence below most accurately describes these enzymes?

A.

They inactivate all ?-lactam antibiotics.

B.

Although they are produced by many isolates of E. coli, such ?-lactamases are not produced by other Gram-negative rods.

C.

They cause resistance to aminoglycosides as well as b-lactams.

D.

They have spread from Gram-negatives like E. coli to Gram-positive pathogens like

E.

*Genes which encode them are often present on conjugative plasmids.

1036.

Material from a patient with suspicion on an intestinal infection was inoculated on the Ploskirev medium. What color do colonies of Escherichia coli have?

A.

dark blue

B.

colorless

C.

brown

D.

green

E.

*red

1037.

Material from a patient with suspicion on typhoid fever was inoculated on Endo medium. What color do colony of lactose-negative Salmonella typhi have?

A.

dark blue

B.

red with metallic hue

C.

brown

D.

green

E.

*colorless

1038.

Microbiologists (using the Kauffman-White classification) report that an outbreak has been caused by Salmonella enterica, serotype Newport. Structure of which pair of antigens determined the serotype as Newport?

A.


B.


C.


D.


E.


1039.

On the Endo medium colonies of Escherichia and Salmonella were isolated. According to what signs is it possible to make differentiation between them?

A.

sizes

B.

character of the edges

C.

character of surfaces

D.

consistency

E.

*color

1040.

Salmonella typhi, which utilizes glucose to acid was inoculated in Ressel medium. What changes will be observed in nutrient medium, which verify utilization of glucose?

A.

Changes of the color from a pinky to dark blue of the slant surface of agar

B.

Changes of the color from a pinky to red of the slant surface of agar

C.

Changes of the color from a pinky to dark blue in the column of agar and slant part of agar

D.

Changes of the color from a pinky to red in the column of agar

E.

*Changes of the color from a pinky to dark blue in the column of agar

1041.


A.

Non-typhoidal Salmonella

B.


C.


D.

Non-cholera Vibrio.

E.


1042.

The main effect of E. coli and Vibrio cholerae enterotoxin on host cells of the gastrointestinal tract that leads to the pathology of the diseases, is to

A.


B.


C.


D.


E.


1043.

The portion of lipopolysaccharide (endotoxin) molecule that is responsible for a bacterial antigenic specificity, as well as the existence of multiple serotypes (serovars) among Gram-negative pathogens, is

A.

lipid A

B.

KDO

C.

R antigen

D.

H antigen

E.

*O antigen

1044.


A.


B.


C.


D.

Nucleic acids

E.


1045.

What color does acquire the semi-solid Hiss media with the rosolic acid as indicator when bacteria utilize sugar?

A.

*red

B.

green

C.

brown

D.

a color does not change

E.

dark blue

1046.

What end products do appear in the liquid Hiss media after fermentation of sugars by E. coli?

A.

acid

B.

alkali

C.

gas

D.

fixing the finished goods is not succeeded

E.

*acid and gas

1047.

What end products does appear in the semi-solid Hiss media after sugar utilization by

Salmonella?

A.

alkali

B.

gas

C.

acid and gas

D.

fixing the finished products is not succeeded

E.

*acid

1048.

What nutrient medium is it possible to use for examination of bacterial proteolytic properties?

A.

Endo medium

B.

Olkenitsky medium

C.

MPB

D.

Levenshtein-Yensen medium

E.

*Milk

1049.

What virulence factor of E. coli is associated with adhesion in the urinary and gastrointestinal tracts and also binds to a blood group antigen?

A.

Colonizing factor antigens

B.

Aggregative adherence fimbriae

C.

Intimin

D.

Ipa protein

E.

*pili

1050.

When ampicillin was first introduced, most E. coli isolates were clinically sensitive. Many isolates are now ampicillin-resistant because they produce ?-lactamases. Which phrase below most accurately describes these enzymes?

A.

Although they are produced by many isolates of E. coli, such ?-lactamases are not produced by other Gram-negative rods.

B.

They inactivate all ?-lactam antibiotics.

C.

They cause resistance to aminoglycosides as well as b-lactams.

D.

They have spread from Gram-negatives like E. coli to Gram-positive pathogens like

E.

*Genes which encode them are often present on conjugative plasmids.

1051.

Which bacteria can produce on Endo medium dark pink colonies?

A.

Salmonella enterica

B.


C.

Shigella sonnei

D.


E.

*Escherichia coli

1052.

Which of the following bacteria belong/s to the family Enterobacteriaceae?

A.

Shigella.

B.

Salmonella.

C.

Yersinia.

D.

Proteus

E.

*All answers are true

1053.


A.


B.


C.


D.

motile, anaerogenic, lactose fermenting, sporulated

E.


1054.

Which of the following does not occur when an individual is infected with Salmonella enteriditis?

A.

Endo toxins cause inflammation and fever

B.

Enterotoxins cause diarrhea

C.

Cytotoxins lyse Endo thelial cells lining the intestinal tract

D.


E.

*Proteolytic enzymes cause necrosis

1055.

Which of the following expresses a Shiga toxin which disrupts protein synthesis, leading to destruction of intestinal villus and decreased absorption with an increase in fluid secretion?

A.

Vibrio cholerae

B.


C.

ETEC

D.

EIEC

E.

*EHEC

1056.

Which of the following Gram-negative rods ferment glucose, are oxidase negative, ferment lactose, and are indole positive (tryptophan metabolizing)?

A.

Shigella

B.

K. pneumoniae

C.

Salmonella

D.

P. vulgaris

E.

*E.coli

1057.

Which of the following Gram-negative rods would indicate a positive MacConkey test in the lactose fermentation?

A.

Shigella

C.

pneumoniae

B.

Salmonella

C.

P. vulgaris

D.

*E.coli

1058.

Which of the following has pathogenesis mediated by cytotoxic Shiga toxins as opposed to plasmid-mediated?

A.

Enteropathogenic E. coli (EPEC)

B.

Enterotoxigenic E. coli (ETEC)

C.

Enteroinvasive E. coli (EIEC)

D.

Enteroaggregative E. coli (EAEC)

E.

*Enterohemorrhagic E. coli (EHEC)

1059.

Which of the following interacts with G proteins that control adenylate cyclase, leading to the catabolic conversion of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP), resulting in a hypersecretion of water and electrolytes?

A.

Vibrio cholerae

B.


C.

ETEC

D.

EHEC

E.

*EIEC

1060.

Which of the following is an important cause of hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS) in the United States?

A.


B.

Enterotoxigenic E. coli (ETEC)

C.


D.


E.

*Enterohemorrhagic E. coli (EHEC)

1061.

Which of the following is most associated with infant diarrhea in underdeveloped countries; watery diarrhea and vomiting, and non-bloody stools?

A.

Enterotoxigenic E. Coli (ETEC)

B.

Enterohemorrhagic E. coli (EHEC)

C.


D.


E.

*Enteropathogenic E. coli (EPEC)

1062.

Which of the following is most associated with Traveler diarrhea; infant diarrhea in developing countries; watery diarrhea, vomiting, cramps, nausea, and low-grade fever?

A.


B.

Enterohemorrhagic E. coli (EHEC)

C.


D.


E.

*Enterotoxigenic E. coli (ETEC)

1063.

Which of the following produces heat-labile (LT-I and LT-II) and heat-stabile (STa and STb) enterotoxins that stimulate hypersecretion of fluids and electrolytes?

A.

Vibrio cholerae

B.

EHEC

C.


D.

EIEC

E.

*ETEC

1064.

Which of the following serotypes of Salmonella can cause gastroenteritis?

A.

S. enteritidis.

B.

S. Newport.

C.

S. typhimurium.

D.

S. cholerae suis

E.

*All answers are true.

1065.


A.


B.


C.

citrate utilization

D.


E.

*motility

1066.


A.


B.


C.


D.


E.

*Escherichia coli

1067.

Which one of the following organisms that in fects the gastrointestinal tract is the MOST frequent cause of bacteremia?

A.

Shigella flexneri

B.


C.

Vibrio cholerae

D.

Salmonella typhi

E.

*All answers are true

1068.

What molecule (endotoxin of Gram-negative pathogens) are responsible for a bacterial antigenic specificity, as well as the existence of multiple serotypes (serovars)?

A.

lipid A

B.

K antigen

C.

R antigen

D.

H antigen

E.

*O polysaccharide

1069.


He now has a fever and abdominal pain. You are concerned that he may have peritonitis. Which one of the following pairs of organisms is MOST likely to be the cause?

A.


B.


C.


D.


E.


1070.

What is the main effect of E. coli and Vibrio cholerae enterotoxin on host cells of the gastrointestinal tract that leads to the pathology?

A.


B.


C.


D.


E.


Situation tasks

1.


A.

Colon

B.

*Nose

C.

Throat

D.

Vagina

E.

Smalll intestine

2.

Residents of an assisted-living facility are immunized against Streptococcus pneumoniae. What is the antigenic component of the vaccine?

A.

A protein toxoid.

B.

Killed whole bacteria.

C.

Live bacteria of attenuated virulence

D.

Purified toxin.

E.

*Purified capsular polysaccharides.

3.

A patient with septicemia goes into septic shock. Blood cultures later show the pathogen to be Neisseria meningitidis. Which component of the bacteria was most likely to be responsible for producing shock?

A.


B.

Teichoic acid.

C.


D.


E.


4.

A child develops ‘strep throat’ (pharyngitis caused by Streptococcus pyogenes). The pediatrician explains to the child’s mother that the pharyngitis normally resolves spontaneously but nevertheless it is important the patient take a full course of Penicillin G. Why is this antibiotic treatment recommended in this situation?

A.

Shortens the course of the infection.

B.

Prevents spread of the infection to adjacent sites.

C.

*Prevents sequellae such as acute rheumatic fever.

D.

Stimulates development of protective immunity.

E.

Prevents spread of the infection to others.

5.

A patient has endocarditis produced by an aд-hemolytic Streptococcus. This usually reflects spread of normal flora to the bloodstream. From which site is this isolate most likely to have spread?

A.

Anterior nares.

B.

Facial skin.

C.


D.

Distal urethra.

E.

*Oropharynx.

6.

A nine years-old child develops high fever and stiff neck. A spinal tap is performed. A Gram-stained smear of cerebrospinal fluid reveals many neutrophils and Gram-negative cocci that resemble paired kidney beans within leucocytes. Which organism below is most likely to have caused this infection?

A.

Escherichia coli

B.


C.


D.


E.


7.

A patient presented with upper back pain. MRI imaging demonstrated inflammation of the T8-T9 vertebral bodies consistent with osteomyelitis. A bone marrow biopsy, when cultured, produced colonies of Gram-positive cocci.Colonies on Sheep blood agar were 3-4 mm in diameter, off-white and beta-hemolytic. Colonies on Brain-heart infusion (BHI) agar were 2-3 mm in diameter and goldenyellow. Catalase and coagulase tests were positive. What was the most likely pathogen?

A.


B.


C.


D.


E.

Streptococcus mitis

8.

A 20-year-old women presents at a local clinic with fever and abdominal tenderness. She reports having had unprotected sexual intercourse a few weeks earlier. Gram-negative diplococci are seen in a Gram stain of vaginal secretions; many of the bacteria are inside polymorphonuclear leukocytes. Which virulence factor is most important in aiding this bacterium to initiate infection?

A.


B.

*Adhesive pili.

C.


D.

Endotoxin.

E.

Flagella

9.

After Gram stain of spinal fluid sample from a patient with meningitis Medical personal during microscopy examination detected Gram-negative cocci, many in pairs. Which organism below is most likely?

A.


B.


C.


D.


E.

Escherichia coli

10.

A young man has a large pus-filled abscess on his upper arm but does not go to a doctor. Several days later he is brought to the Emergency Room with fever, hypotension, and multiple organ failure. Which of the following is most likely to be responsible?

A.


B.


C.


D.


E.


11.


A.


B.


C.


D.


E.


12.

Five young men suffer acute attacks of nausea and vomiting a few hours after returning from a student’s party, at which they ate hamburgers, potato salad, and custard pie. By morning all are feeling better.

Which bacterial toxin is most likely to have caused their symptoms?

A.


B.


C.


D.


E.


13.

E. coli and Neisseria meningitidis isolated from blood cultures often have transport systems (for acquiring metal ions from the environment) lacking in their less-virulent relatives. Which metal is acquired by the majority of these systems?

G.

Copper

H.

Sodium

I.

Potassium

J.

Magnesium

K.

*Iron

14.

A 25-year-old woman presents with a swollen, warm, painful knee. Aspirated joint fluid is cloudy and when cultured on chocolate agar gives rise to oxidase-positive colonies of Gram-negative diplococci.


A.


B.


C.


D.


E.

Nocardia asteroides

15.

In cervical specimens of 21-year-old woman presents gram-negative diplococci within leucocytes.


A.


B.


C.


D.


E.

Nocardia asteroides

16.

A workman has a large pus-filled lesion on the left forearm, tender, red, and swollen. It is incised. A smear of the pus is Gram-stained. Many neutrophils are seen, also many Gram-positive cocci, most in large clusters. The organism is b-hemolytic on sheep blood agar. Colonies are pale-yellow, opaque, and shiny, with neat round outlines. Of the bacteria listed below, which is most likely to have produced the abscess?

A.

Streptococcus bovis

B.


C.

Streptococcus mitis

D.


E.


17.

A young man complaines on pain on urination and profuse purulent discharge from his urethra. Gram stain of the discharge revealed large numbers Gram-negative cocci, mostly in pairs within neutrophils.

Which bacterium is most likely to have caused his infection?

A.

Mycoplasma hominis

B.


C.


D.


E.

Treponema pallidum

18.

A 17-year-old sexually-active male presents with a four-day history of pain on urination and profuse purulent discharge from his urethral opening. Gram stain of the discharge revealed large numbers of neutrophils. A small fraction of neutrophils contained Gram-negative cocci, mostly in pairs. Which bacterium is most likely to have caused his infection?

A.

Mycoplasma hominis

B.


C.

Treponema pallidum

D.


E.


19.

An 18-year-old high school student has a large pus-filled lesion on the left forearm, tender, red, and swollen. It is incised, drained, washed, and bandaged. A smear of the pus is Gram-stained. Many neutrophils are seen, also many Gram-positive cocci, most in large clusters. The organism is bhemolytic on sheep blood agar. Colonies are pale-yellow, opaque, and shiny, with neat round outlines.

Of the bacteria listed below, which is most likely to have produced the abscess?

A.


B.


C.

Streptococcus mitis

D.


E.

Streptococcus bovis

20.


A.


B.


C.


D.


E.


21.


A.


B.


C.


D.


E.


22.

An elderly man develops pneumonia and septicemia. Gram stain of sputum contains many neutrophils and Gram-positive cocci, in pairs. Blood and sputum cultures grow out a Gram-positive coccus, ?hemolytic on sheep blood agar, and catalase-negative. Which organism below is most likely?

A.


B.


C.


D.


E.


23.


A.


B.


C.


D.


E.


24.

A 23-year-old medical student had headache and fever one evening. By the next morning she had become very ill, with high fever, severe headache, and stiff neck. She was admitted to the hospital. Later that day she developed rash, at first petechial and then pupuric. Gram stain of CSF showed many white cells and Gram-negative cocci, many in pairs. Which organism is most likely to be the cause of her infection?

A.

Escherichia coli.

B.


C.


D.


E.


25.


A.


B.


C.


D.


E.


26.

Untreated pharyngitis produced by Group A streptococci can result in later development of Acute rheumatic fever, created by cross-reaction of anti-streptococcal antibodies with heart tissue. Which streptococcal antigen stimulates formation of these cross-reactive antibodies?

A.

A.Group A carbohydrate.

B.

Flagella.

C.

*M protein

D.

Peptidoglycan.

E.

Teichoic acid.

27.


Streptococcus?

A.


B.

Bile-esculin test.

C.


D.


E.


28.


A.


B.


C.


D.


E.


DNA.

29.


A.

M-proteins.

B.


C.


D.


E.


30.


A.


B.

Gall bladder.

C.

Large intestine.

D.

*Nasopharynx.

E.


31.


A.


B.


C.


D.


E.


32.

Two hours after a delicious Thanksgiving dinner of barley soup, roast turkey, stuffing, sweet potato, green beans, cranberry sauce, and pump kin pie topped with whipped cream, the Smith family of four experience vomiting and diarrhea. Which one of the following organisms is MOST likely to cause these symptoms?

A.

Shigella flexneri

B.


C.


D.


E.

All are true

33.

An 81-year-old man with chronic emphysemea and hypertension develops fever, chills, and respiratory distress. X-rays show lobar pneumonia. Sputum smear contains numerous Gram-positive cocci, many of which are in pairs. Sputum culture on Sheep blood agar produces many colonies of an alpha-hemolytic

Gram-positive coccus. It is catalase-negative, Bile-esculin negative, and optochin-sensitive. Which of the organisms below is most likely?

A.


B.


C.

Streptococcus mitis

D.


E.


34.


A.


B.


C.

Streptococcus mitis

D.


E.


35.

A 75-year-old man reports malaise, headache, and fever. On examination his neck is stiff. Gram stain of

CSF reveals neutrophils and numerous Gram-negative cocci, many in pairs.Which organism below is most likely?

A.


B.


C.


D.


E.


36.


A.


B.


C.


D.

Mycoplasma hominis.

E.

Treponema pallidum.

37.


A.

Salmonella

B.

ETEC

C.

Shigella

D.

Yersinia

E.

*Campylobacter

38.


A.


B.

Escherichia coli.

C.


D.


E.


39.

A 40-years-old patient has a peptic ulcer. Which organism is most likely to have created this lesion?

A.


B.


C.

Escherichia coli.

D.


E.


40.


A.

Rare hamburger.

B.

Dog or cat.

C.


D.


E.

*Another child.

41.


A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

42.


A.


B.


C.


D.


E.


43.

A four-year-old boy was brought to the emergency room with a history of bloody diarrhea over the preceding two days. A fecal smear contained numerous red cells and neutrophils. Stool culture on Endo agar produced lactose-negative colonies amid colonies of ‘normal intestinal flora’. Which of the organisms below is most likely to be the cause of his illness?

A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

44.


A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

45.


A.


B.


C.

phagotyping

D.


E.


46.

A middle aged man recently returned from visiting his family in India develops severe diarrhea. He in fact has cholera. His diarrhea is produced by a protein exotoxin secreted by Vibrio cholerae. How does this toxin act?

A.


B.


C.


D.


E.


47.


A.


B.


C.


D.

Vibrio cholerae

E.

*Shigella sonnei

48.


A.


B.

pink colonies

C.

black colonies

D.


E.


49.


A.


B.


C.


D.

Escherichia coli.

E.


50.

A patient has been diagnosed with a gastric ulcer. A test of the patient's serum shows reactivity with

Helicobacter pylori antigens. Which of the following is true?

A.


B.


C.

All are true

D.


E.


51.


A.

Escherichia coli.

B.


C.


D.


E.


52.


A.

tetracycline

B.

toxoid

C.

vaccine

D.

antiserum injection

E.


53.


A.


B.


C.


D.


E.



54.


A.

Rare hamburger.

B.


C.

Dog or cat.

D.


E.

*Another child.

55.


A.


B.


C.

serotherapy

D.

vaccination

E.


56.

A young woman got cholera. To determine to which species the infectious agent belongs, the microbiologist performs some tests on colonies cultured from stool samples. These tests include the following EXCEPT:

A.


B.


C.


D.


E.


57.

Among the Sunday night patients at the Smithville emergency room were ten young adults suffering from severe diarrhea. All are true individuals would normally characterize themselves as being in good health. All reported eating at a local Dairy fair during the weekend. Of the following bacterial species the least likely to be responsible is

A.

Campylobacter fetus

B.

Shigella flexneri

C.


D.


E.


58.


A.


B.


C.


D.


E.


59.

From a 29-year-old stressed-out medical student with gastritis a urease-positive, spiral-shaped gramnegative rod is found in gastric washings. Which of the following is most likely to be this organism?

A.

Proteus mirabilis

B.


C.

Vibrio cholerae

D.


E.


60.


A.

milk

B.

poultry

C.

chicken

D.

clams

E.

*hamburger

61.

Gastroscopy reveals that a patient with stomach pain has a large ulceration of his gastric mucosa. During the procedure a biopsy of the stomach epithelium is obtained. Which observation would suggest


A.


B.


C.


D.


E.


62.

Healthy adult travelers visiting Peru are cautioned against eating uncooked vegetables and unpeeled fruits, and against drinking unbottled water. However, they are already resistant to cholera because of:

A.


B.


C.


D.


E.


63.


A.


B.

pink colonies

C.

black colonies

D.


E.


64.


A.

Salmonella

B.

Yersinia

C.

ETEC

D.

Shigella

E.

*Campylobacter

65.


A.


B.


C.


D.


E.


66.


A.

V. parahaemolyticus

B.

V. alginolyticus

C.

V. vulnificus

D.

V. cholerae non 01

E.

*V. fluvialis

F.


67.

Your patient is a 30-year-old woman who was part of a tour group visiting a N. country. The day before leaving, several members of the group developed fever, abdominal cramps, and bloody diarrhea. Of the following, which one is the LEAST likely organism to cause this infection?

A.


B.

Vibrio cholerae

C.


D.


E.


68.

Your patient is a 30-year-old woman who was part of a tour group visiting a N. country. The day before leaving, several members of the group developed fever, abdominal cramps, and bloody diarrhea. Which of the following bacterium is causative agent of dysenteriae?

A.

Klebsiella

B.

Proteus

C.

E. coli

D.

Vibrio

E.

*Shigella

69.

cholera. His diarrhea is produced by a protein exotoxin secreted by Vibrio cholerae. How does this toxin act?

A.


B.


C.


D.


E.


70.


A.

Rare hamburger.

B.

Dog or cat.

C.


D.

*Another child.

E.


71.


A.

Frequent presence in the upper respiratory tracts of children who are not ill.

B.


C.


D.


E.


72.


A.


B.


C.


D.

Escherichia coli.

E.


73.

Gastroscopy reveals that a patient with stomach pain has a large ulceration of his gastric mucosa. During the procedure a biopsy of the stomach epithelium is obtained. Which observation would suggest


A.


B.


C.


D.


E.


74.

to remove non-living bacterial components. Of those listed below, which is the most toxic?

A.


B.


C.


D.


E.

Nucleic acids

75.

A stool sample is plated on standard Endo-agar plates. After overnight incubation some of the colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the bacteria that produced dark-pink colonies?

A.

Gram-positive.

B.

*Ferment lactose.

C.


D.

Non-motile.

E.

Produce capsules

76.


A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

77.


A.


B.


C.


D.


E.


78.


A.


B.


C.

Escherichia coli.

D.


E.


79.

A 6 years old child has paroxysmal cough during 3 days. Whooping cough was diagnosed. What tested material for examination is it needed to take first to confirm a diagnosis?

A.

Patient’s blood

B.

*Smear from the posterior wall of the throat

C.

Pus

D.

Patient’s serum

E.

Vomiting masses

80.

A baby was born in a maternity hospital. What vaccine is prescribed him before discharge from a hospital?

A.


B.

Attenuated poliomyelitis vaccine

C.

EV 76 vaccine

D.

Attenuated influenza vaccine

E.

*BCG

81.

A child has a common cold which progresses to severe pharyngitis. Pharyngeal exudate forms a tough membrane difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which organism is most likely to have caused this infection?

A.


B.


C.

Candida albicans.

D.


E.


82.

A child has severe pharyngitis. Pharyngeal exudate forms a tough 'membrane', difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which organism below is most likely to have caused this infection?

A.


B.


C.


D.

Mycobacterium avium/intracellulare

E.


83.

A girl, 7 years of old was admitted to the hospital with the high temperature, throat pain general weakness. A doctor suspected diphtheria and took material from pharynx for isolation of pure culture of

Corynebacterium. What test can confirm the diagnosis of diphtheria?

A.

Examination of volutin granules

B.

Examination of cystinase production

C.

Examination of hemolytic properties

D.

Susceptibility to phages

E.

*Examination of bacterial toxigenicity

84.

A growth of tuberculosis bacteria on nutrient media takes a place in 3 weeks, sometimes in 2-3 months.

But express technique for there cultivation, Prices and Shkolnikov’s methods may be used. In what time is it possible to get growth of tuberculosis microcultures?

A.

3-4 days

B.

20-30 days

C.

over 40 days

D.

over 50 days

E.

*7-10 days

85.

A man, 40 years old has chronic kidneys infection. During examination of urine acids fast rod-shaped microbes were revealed. They did not grow on simple nutrient media, but on Loewenstain-Jensen medium in a few weeks they formed dry yellowish colonies. What group of microorganisms could cause his disease?

A.

Chlamidia

B.

Mycoplasma

C.

Trichomonas

D.

Gardnerella

E.

*Mycobacteria

86.

A microbiologist put a few drops of 1% Ziehls phenol fuchsine on a paper which covers a smear from patients sputum, heat it until steam rose. He repeated this procedure three times. Then took off a paper, put a smear in 5 % sulphuric acid, washed with water and stained by methylene blue. What microbes can be examined by this technique?

A.

S. aureus

B.

S. pneumoniae

C.

S. viridans

D.

K. pneumoniae

E.

*M. tuberculosis

87.

A mother with a 5 years old girl, who has a cough and flu-like state during 2 weeks, visited the doctor.

Last time a cough increased, paroxysmal cough appeared. A doctor diagnosed whooping-cough. What factors do determine virulence of Bordetella pertussis?

F.

Exotoxin

G.

Pili

H.

Hyaluronidaze

I.


J.

*Thermolabile toxin

88.

A patient has cough with discharges of sputum. During microscopic examination after staining this smear by Ziehl-Neelsens technique dark blue cocci, which form irregular clasters and rod-shaped red bacteria were revealed. What microorganisms may be a reason of disease?

A.

Actinomyces bovis

B.


C.

E.coli

D.


E.


89.

A sick child was tested by Mantouxs test. In 24 hours there were tumidity, hyperemia and painfulness in the place of allergen injection. What basic mechanisms do provide this reaction of a body?

A.

Granulocytes, T- lymphocytes, and Ig G.

B.

Plasma cells, T-cell, and lymphokines

C.

B-lymphocytes, IgM

D.

Macrophages, B-lymphocytes, and monocytes

E.

*Mononuclear cells, T-cell, and lymphokines

90.

After making Mantouxs test in a child of 4 years old in 72 hours a reddening of the skin in the place of injection of tuberculin is not observed. What does this result testify?

A.

A child has tuberculosis

B.

A child is vaccinated against tuberculosis

C.

A child is a carrier of tuberculosis bacteria

D.

A child is infected by tuberculosis bacteria

E.

*A child is not vaccinated against tuberculosis

91.

After staining of patient’s sputum by Ziehl-Neelsen technique red rod-shaped bacteria were revealed.

The first signs of bacterial growth appeared in 17 days. What bacteria may be there in the smear?

A.

Yersinia pseudotuberculosis.

B.

Histoplasma dubrosii

C.

KlРµbsiella rhinoscleromanis

D.

Coxiella burnetii

E.


92.

After vaccination of babies by BCG vaccine immunity to tuberculosis lasts until there are living bacteria of vaccine strain in an organism. What is correct name of such type of immunity?

A.

Type specific

B.

Humoral

C.

Species inherited

D.

Natural

E.

*Non-sterile

93.

Bacteriological laboratory urine from a patient with an initial diagnosis of kidneys tuberculosis must be investigated in bacteriological laboratory. What method of diagnosis is it better to utilize?

A.

Bacteriological

B.

Bacterioscopy

C.

Serological

D.

Allergic

E.

*Biological

94.

9 years old has diphtheria of pharynx. What was the way of diphtheria transmission?

A.

Fecal-oral

B.

*Air born

C.

Sexual

D.

Contact

E.

No way

95.

Diphtheria was diagnosed in 4 years old child. What preparation is it necessary to inject first of all?

A.

TABTe.

B.

Diphtherial toxoid

C.


D.

Vaccine against diphtheria and tetanus

E.

*Diphtherial antiserum.

96.

During examination of bacterial carriers in the kindergarten one nurse showed the presence of

Corynebacterium in her throat. The production of toxin by Corynebacterium diphtheriae was checked.

It did not produce exotoxin. What test was used for examination of toxigenicity?

A.

Agglutination test

B.


C.


D.


E.

Immunofluorescence test

97.

During examination of patient’s sputum, which was inoculated by Prices technique, rod-shaped bacteria appear as plaits. What substance from tuberculosis bacilli does form such pictures?

A.

Tuberculin.

B.

*Cord-factor

C.

Phtionic acid (phosphatide).

D.

Fatty acids.

E.

PPD.

98.

During the examination child 6 years of old a doctor noticed greyish film on the surface of tonsils.

During the attempt of it’s deleting moderate bleeding appeared. During bacterioscopy after Neissers staining: rods display club-shaped swellings, volutin granules. What symptoms will appear in a child in the nearest days, if specific treatment will not be prescribed?

A.

Oedema of lungs

B.

*Toxic lesion of cardiac muscle and kidneys

C.

Paroxysmal cough

D.

Papular rashes on a skin

E.

Disorders of digestion

99.

Every year pediatricians use Mantouxs allergic for checking of the children and teenagers. What is the aim of this test?

A.

Treatment of tuberculosis

B.

Prophylaxis of tuberculosis

C.

Vaccination

D.

*A selection of children for revaccination by BCG vaccine

E.

No correct answer

100.

Five days old boy has planned immunization with BCG vaccine. In 7 years doctor prescribed repeated immunization with the same vaccine. What examination was the basis of such doctor’s decision?

A.

Examination of antimycobacterial antibodies

B.

*Skin allergic test

C.

Medical and genetic examination

D.

Bacterioscopy of childs sputum

E.

X-ray examination of the lungs

101.

Five years old child was admitted to the hospital with a diagnosis of diphtheria of pharynx.

Material, which was taken from greyish film on tonsils, was inoculated Klaubergs medium. What are there properties of Corynebacterium colonies on this medium?

A.

Colonies are convex, with even edges, colorless

B.

Colonies are rounded, concave in a center, white

C.

Colonies are protuberant, viscid, remind a shagreen skin, grey

D.

Colonies are rosette-like, a surface is knobby, yellow

102.

E.

*Colonies are grey, round, rosette-like

In 6 years old child with paroxysmal cough mucous from oropharynx was taken. This material was inoculated on glycerin-potatoes agar. In 72 hrs of cultivation at 37 C there were small greyish convex, and glistening, resembling globules of mercury appeared. What causative agent did cause this disease?

A.


B.


C.


D.

*Bordetella pertussis

E.

Mycobacteria tuberculosis

103.

In 8 years old child active tuberculosis process was suspected. Diagnostic Mantouxs reaction was made. In 30 minutes after the injection there was an insignificant erubescence in the place of injection. In 24 hours the phenomenon of dermahemia disappeared. What does the result of reaction testify to?

A.

Postvaccinal immunity

B.

Active tubercular process.

C.

*A reaction is negative

D.

A tuberculosis process is occult

E.

A reaction is positive

104.

In a 6 years old child active tuberculosis process was suspected. Diagnostic Mantouxs reaction was made. What immunobiological preparation was used?

A.

Pertussis-diphtheria-tetanus vaccine.

B.

BCG vaccine.

C.

*Tuberculin.

D.

Tulyarin.

E.

No correct answer

105.

In a child with the suspicion of diphtheria a swab from the mucus membrane of pharynx was taken. After staining by Loeffers method dark-blue granules of volutin were revealed in bacteria. What value does their examination have?

A.

*Diagnostic

B.

Treatment

C.

Prophylactic

D.

None of them

106.

E.

All answer are correct

In a maternity hospital it follows newborn to execute an inoculation against tuberculosis. What preparation must be here utilized?

A.

Vaccine of EV.

B.

Vaccine of STI

C.

*Vaccine of BCZH

D.

Vaccine of AKDP

E.

Tuberculin

107.

In a smear from a patients tonsils with suspicion of diphtheria blue rod-shaped bacteria display terminal club-shaped swellings, which stained more intensely at their end were revealed. What method of staining was utilized?

A.

Gram

B.

Burry

C.

Giemsa

D.

*Loeffler

E.

Neisser

108.

In an infectious department there is a girl, 10 years of old with a diagnosis diphtheria of pharynxвЂќ. Toxigenic strain of Corynebacterium diphtheriae was isolated. How can you examine the strain toxigenicity?

A.

By agglutination test

B.

By complement fixation test

C.

*By precipitation test in a gel

D.

By indirect haemagglutination test

109.

E.

By flocculation test

In kindergarten whooping cough was diagnosed in 3 children. In what clinical periods of whooping cough they may be most contagious?

A.

Latent period

B.

Paroxysmal period

C.

*Catarrhal period

D.

Regenerative period

110.

E.

Period of reconvalescence

Patient has initial diagnosis of lung tuberculosis. What nutrient medium may be used for isolation of mycobacteria:

A.

glycerin-potatoes agar

112.

B.

*Loewenstein-Jensen medium

C.

salt-salt agar

D.

blood agar

E.

Ploskirev medium

111.

Patients sputum was sent to a laboratory. What method of staining does it follow to utilize for the examination of causative agents of tuberculosis?

A.

Gram

B.

Giemza-Romanovsky

C.

Gins-Burry

D.

*Ziehl-Neelsen

E.

Neissers

Seven years old child has fever and paroxysmal cough. Similar symptoms were observed in a senior brother month ago. There may be whooping cough. What method is it possible to use for retrospective diagnosis of this disease?

A.

*Serological

B.

Bacteriological

C.

Biological

D.

Morphological

E.

Allergic

113.

The child has diagnosis of diphtheria of pharynx. The clinical diagnosis is confirmed by bacteriologic examinations: toxigenic Corynebacterium diphtheria was isolated. What preparations do apply for specific treatment?

A.

Antibiotics

B.

Sulfonamides

C.

Toxoid

D.

*Antitoxic serum

114.

E.

NO correct answer

There is 7 years old child with a diagnosis of diphtheria of pharynx. What tested material must be taken for isolation of causative agent and confirmation of diagnosis?

A.

Patients blood

B.

Patients serum

C.

*Swab from the pharynx

D.

Sputum

115.

E.

Pus

There is a bacteriological method for laboratory diagnosis of diphtheria. For cultivation of РЎ. diphtheriae it is necessary to know the some bacterial properties. What nutrient media it is necessary to

116.

use for cultivation of Corynebacterium diphtheriae?

A.

Serum agar

B.

*blood agar, blood tellurite agar

C.

sugar MPB, sugar MPA

D.

yolk-salt agar

E.

Endo, Ploskirev

When doctor examined a child of 6 years old he revealed the greyish film on the tonsils. He took this film, stained by Neisser's technique. What morphological feature was most substantial for confirmation that these microbes are Corynebacteria?

A.

Localization of microbes in macrophages

B.

*The presence of volutin granules at the ends of microbes

C.

Presence of spores, their diameter is more then diameter of the cell

D.

Presence of flagella

E.

Presence of capsule

117.


A.


B.


C.


D.


E.


118.

119.

ANSWER:A

A 22-year-old develops an abscess in his peritoneum following rupture of his appendix. Gram stain of exudate from his foul-smelling abscess reveals numerous polymorphonuclear leukocytes, Grampositive cocci, Gram-positive rods, and Gram-negative rods. Aerobic culture of the exudate at 37oC on blood and MacConkey agar yields only Enterococci. Which of the bacteria below is most likely to be

120.

the Gram-negative rods seen in the stained smear?

A.


B.

Proteus mirabilis.

C.


D.


E.




A.


B.


C.


D.

Clostridium tetani.

E.


121.


A.


B.


C.


D.

Clostridium tetani.

122.

E.



A.


B.


C.


D.


123.

E.



A.


B.

Innate and humoral.

C.


D.


124.

E.


A 20-year-old student has a deep laceration. He received the standard four-doses of Diphtheria-

Pertussis-Tetanus immunizations in infancy, and a booster at age 5, but has had no anti-Tetanus

125.

immunization since. Which of the following would it be most appropriate to administer?

A.

Tetanus toxoid.

B.

Tetanus anti-toxin (equine).

C.

Tetanus immune globulin (human).

D.

*Both Tetanus toxoid and Tetanus immune globulin (human).

E.

Both Tetanus toxoid Tetanus anti-toxin (equine).

A ten-year-old girl has dirty, crushing, wounds, received when she fell from a motorcycle. She has never been immunized against Tetanus. Which of the following should you administer?

A.

Tetanus immune globulin (human) Tetanus toxoid

B.

Tetanus anti-toxin (equine) Tetanus toxoid

C.

Tetanus toxoid Tetanus immune globulin (human)

D.

Tetanus toxoid plus Tetanus immune globulin (human),

E.

*Tetanus toxoid plus Tetanus immune globulin (human

126.


A.

Bacillus anthracis.

B.

Bacillus cereus.

C.


D.


127.

E.



A.


B.


C.


D.


128.

E.



A.


B.

Diphtheria.

C.

Anthrax.

D.

*Botulism.

129.

E.

Tetanus.


A.


B.

*Tissue ischemia.

C.


D.


E.


B.

A 50-year-old woman was treated for cystitis [caused by E. coli] with an oral broad-spectrum antibiotic.

Three weeks later she developed abdominal pain and diarrhea. A stained smear of stool contained many neutrophils. Cultures for bacterial pathogens were negative. A serological test of stool for Clostridium difficile toxin was positive. Which of the following is most likely to have been the immediately predisposing cause of this patient’s C.difficile infection?

F.


G.


H.


I.


J.

All are true

130.


He now has a fever and abdominal pain. You are concerned that he may have peritonitis. Which one of

131.

the following pairs of organisms is MOST likely to be the cause?

A.


B.


C.


D.


E.

All are true



A.


B.


C.

Proteus mirabilis

D.


E.

All are true

132.

Laboratory assistant has to isolate Clostridium tetani, anaerobic sporeforming bacterium, from wound exudation. What will he do before inoculation of material into appropriate culture medium?

A.


B.


C.


D.


133.

E.




134.


A.


B.


C.

Proteus mirabilis

D.


E.

Clostridium tetani.

A 55-year-old woman develops diplopia, one day after eating home-canned fruit. (Diplopia * double vision, from inability to coordinate the direction of gaze of the eyes.) A few hours later she develops difficulty speaking, bilateral weakness of her arms, nausea, vomiting, dizziness, blurred vision, and dry mouth. However she is alert, oriented, and has no fever. If this is botulism, by what mechanism did Clostridium botulinum produce her signs and symptoms?

A.

Bound to Toll-like receptors and stimulated production of inflammatory cytokines.

B.

Injected proteins into neurons via a type III secretion system.

C.

*Secreted a protein toxin that enters mammalian neurons and blocks synaptic transmission.

D.

Released peptidoglycan and other inflammatory components of the cell envelope.

E.

Bacteremic spread followed by infection of multiple tissues: eyes, muscle, stomach, nervous system, salivary glands.

135.

Home-canned food is a common source of botulism in adults. What property of C. botulinum facilitates infection by this route?

A.

*Produces airborne spores not easily killed by boiling.

B.

Vegetative cells grow best at cooking temperatures.

C.

Extremely resistant to gastric acid.

D.

Thick peptidoglycan renders cells resistant to heat, cold, and drying.

E.

Surface proteins inhibit digestive hydrolases.

136.


A.


B.

*Tissue ischemia.

C.


D.


137.

E.




A.


B.


C.


D.

Clostridium tetani.

E.


138.

Surgeon has suspected anaerobic wound infection. To isolate causative germs collected wound discharge should be cultivated into the such medium as :

A.

Ploskirev agar

B.

*Kitt-Tarozzi medium

C.

meat peptone broth

D.

Endo agar

E.

meat peptone agar

139.

Laboratory assistant has to isolate Clostridia tetani, anaerobic sporeforming bacterium, from wound exudation. What will he do before inoculation of material into appropriate culture medium?

A.


B.


C.


D.


140.

E.




A.


B.


C.

Proteus mirabilis

D.


141.

A young man develops peritonitis following abdominal trauma. During surgery foul-smelling purulent material is aspirated from the infected area. Gram stain of this material contains a mixture of

Grampositive cocci, Gram-positive rods, and many Gram-negative rods. Aerobic culture on sheep blood agar yields many colonies of enterococci and a few colonies of E. coli; culture on MacConkey agar produces only sparse colonies of E. coli. Anaerobic culture on sheep blood agar produces a few colonies of beta-hemolytic Gram-positive rods and many colonies of slender Gram-negative rods. Which organism is most likely to represent the majority of the Gram-negative rods seen when peritoneal exudate was stained?

A.

Yersinia enterocolitica

B.


C.

Clostridium tetani

D.

Yersinia pseudotuberculosis

142.

E.


A diabetic 78-year-old man develops a necrotic ulcer on his right foot. Infection spreads rapidly and there is gas in soft tissues. His foot is amputated at the ankle. Gram stain of exudate from the amputation site contains large Gram-positive rods. The bacteria grow well anaerobically, producing large ?-hemolytic colonies on sheep blood agar, but do not grow aerobically. What organism is most probable in this setting?

A.

Bacillus cereus

B.


C.

Nocardia asteroides

D.

Clostridium tetani

143.

E.



A.


B.


C.


D.


144.

E.

Binding of neurotransmitter molecules to their receptors.

A 50-year-old woman was treated for cystitis [caused by E. coli] with an oral broad-spectrum antibiotic. Three weeks later she developed abdominal pain and diarrhea. A stained smear of stool contained many neutrophils. Cultures for bacterial pathogens were negative. A serological test of stool for Clostridium difficile toxin was positive. Which of the following is most likely to have been the immediately predisposing cause of this patient’s C. difficile infection?

A.


B.


C.


D.


145.

E.


A security guard at a New Jersey Court House comes to your office with a large lesion on his left arm. It is 10 cm in diameter and ulcerated. Surrounding tissue is red and markedly swollen. The ulcer is healing to produce a black scab. A swab of the ulcer contains large Gram-positive rods. After aerobic

culture on sheep blood agar these produce large alpha-hemolytic colonies. Which organism is most likely?

A.

*Bacillus anthracis

B.

Bacillus cereus

C.


D.

Clostridium perfingens

146.

E.

Clostridium tetani


A.


B.

Diphtheria.

C.

Anthrax.

D.

*Botulism.

E.

Tetanus.

147.

In the United States human Tetanus is now a rare disease. Which measure below has been most important in preventing it?

A.

Vaccination of livestock, especially cattle, with a killed-organism vaccine.

B.

*Immunization of humans with a toxoid-containing vaccine.

C.

Eradication of the organism from the environment.

D.

Sewage treatment and purification of water supplies.

E.

Antibiotic treatment of contacts of patients with C. tetani infections.

148.


A.


B.


C.


149.

D.


E.

Nucleic acids

A 13-year old boy develops pain and marked (10 cm.) swelling in his right inguinal lymph node accompanied by fever of 104oF. He and his family have just returned from a vacation trip to Arizona and New Mexico. Aspirate from the node contains Gram-negative rods. A direct immunofluorescent assay on the aspirate provides a definitive diagnosis. The child is (successfully) treated with streptomycin, and the aspirate is sent for culture to the CDC. Culture yields pale colonies on

MacConkey agar. What is the most probable pathogen?

A.

*Yersinia pestis.

B.

Helicobacteri pylori.

C.


D.

Coxiella burnetii.

E.


150.

A 34-year old person has rapidly developing cough, dyspnoea, expectoration ana blood-tinged sputum, he is febrile, cyanosed and toxic. Chest examination reveals crepitations and rhonchi. The most likely diagnosis is

A.

Legionella pneumonia

B.

*Pneumonic plague

C.

Septicaemic plague

D.

Pulmory tuberculosis

151.

E.

No correct answer

A doctor is struggling to diagnose a woman’s flulike illness. She complains of a fever that rises during the day and peaks after dinner (undulant fever), fatigue, spinal tenderness, and loss of appetite.

Her lymph nodes are enlarged in physical exam. The doctor has trouble narrowing down the possible etiologies until he hears that the tasted goat cheese at a French village a month before the onset of her symptoms. Which of the following is the most likely cause?

A.


B.


C.


D.


E.

Brucella species

152.

A teenage girl enters the emergency room suffering painful muscle spasms. Throughout her examination, she sustains a facial sneer, a stiff arched back, and clamped palms. Her father is anxious about the fact that she has also experienced difficulty eating, probably due to a stiff jaw. The father affirms that her daughter is usually quite active and boasts how, a week ago, she continued a soccer game even after falling on a nail in the field. Which of the following is the most likely cause?

A.

C. difficile

B.

C. perfingens

C.

C. septicum

D.

C. botulinum

153.

E.

*C. tetani

A woman straggles into the emergency room with a marked paralysis of her upper body. She describes the paralysis as a weakness that began in her neck and spread to her arms. She also complains of blurred double vision and requests water to soothe her dry throat. Though she has no fever, she appears quite dizzy and her eyelids are drooping. The day before, she returned from a camping trip where she insists she maintained good hygiene, limiting her diet to canned food only. Which of the following is the most likely cause?

A.

C. difficile

B.

C. perfingens

C.

C. septicum

D.

*C. botulinum

E.

C. tetani

154.

An old woman comes to the doctor with a fever and loose bowels. Her diarrhea occurs in tremendous volumes, she complains, though she doesn’t remember seeing blood. She has an unremarkable recent past medical history, except for an infection a few weeks earlier that was treated with clindamycin. Sigmoidoscopy of her colon reveals yellow-white plaques which the doctor predicted after analyzing her stools for toxins. Which of the following is the most likely cause?

A.

*C. difficile

B.

C. perfingens

C.

C. septicum

D.

C. botulinum

E.

C. tetani

155.

A man enters the emergency room claiming to have been stabbed two days earlier. Muscles in his arm hurt, and on palpation small air bubbles are felt below the skin. The wound area exudes a blackish, ill-smelling fluid that generates a crackling sound when touched. The patient has a fever, a low blood pressure, marked tachycardia, and urina very little since his injury. The doctor decides to amputate the arm, as well as monitor the patient for shock and renal failure Which of the following is

156.

the most likely cause?

A.

C. difficile

B.

*C. perfingens

C.

C. septicum

D.

C. botulinum

E.

C. tetani

A mother brings her 12-year-old son to your office because he has a skin lesion on his back. It is

20 cm in diameter, with a red inflamed border and a red center, with a paler ring between the red areas.

The mother says it has expanded rapidly over the last few days. Which of the following would be most likely to cause such a lesion?

A.


B.

Treponema pallidum

C.


D.

Chlamydia psittaci

157.

E.


A 16-year-old boy has a skin lesion on his back. It is 20 cm in diameter, with a red inflamed border and a red center, with a paler ring between the red areas. He says it has expanded rapidly over the last few days after tick bite. Which of the following would be most likely to cause such a lesion?

A.


B.


C.

Treponema pallidum

D.

Chlamydia psittaci

E.


158.

A patient is diagnosed with pelvic inflammatory disease (PID), you suspect caused by

Chlamydia trachomatis. If you wished to confirm C. trachomatis, which test below should you use?

A.

Culture of urine on broth-based agar at 20?C.

B.

Culture of cervical exudate on chocolate agar in elevated CO2.

C.

Microscopic examination of a stained smear of peripheral blood.

D.

*Gram stain of exudate from the cervix.

E.

PCR-based nucleic-acid amplification test of a cervical swab.

159.


A.


B.


C.


D.


E.


160.

A mother is worried that the child may have contracted Lyme disease. Which finding would most strongly suggest that she is correct?

A.

A disseminated rash, with small papular erythematous lesions.

B.

An ulcer and edema at the site of the tick bite.

C.

A lesion at the site of the tick bite that develops a thick, black, crusted, scab.

D.

*A “bull’s-eye” lesion with erythematous periphery and central clearing.

E.

A sparse red macular rash, on the palms and soles only.

161.


A.


B.


C.


D.


E.


162.

A patient has a positive Rapid Plasma Reagin (RPR) test for ‘non-treponemal antibodies’. A test for specific anti-treponemal antibodies is positive but the patient has no rash, genital lesions, inflammation, or discharge. Which conclusion best follows from these findings?

A.

The patient does not require antibiotic treatment; absence of symptoms indicates that the positive

RPR is a ‘biological false positive”.

B.

The patient has Syphilis, but does not require antibiotic treatment, because infections with

Treponema pallidum normally resolve spontaneously.

C.

The patient has Syphilis, but the diagnosis should be confirmed by culture before antibiotictreatment is started.

D.

*The patient has Syphilis, and should be treated with Penicillin G

163.

E.

No correct answer

In August, a young man presents with a history of fever for 1 week and a red rash which extends to the palms and soles. IgM titer to Rickettsia rickettsii is 1:640. From which vector was this infection

164.

most likely to have been acquired?

A.

*Dog tick.

B.

Mosquito of the genus Anopheles.

C.

Blood-sucking sandfly.

D.

Flea.

E.

Human body louse.

A 25-year-old man complains of a urethral discharge. You perform a Gram stain on a specimen of the discharge and see neutrophils but no bacteria. Of the organisms listed, the one MOST likely to cause the discharge is

A.

Treponema pallidum

B.


C.

Candida albicans

D.

Coxiella burnetii

165.

E.

All are true

An 8-year-old boy living in a wooded area of Virginia suddenly developed fever, headache, and myalgia. On physical exam, a rash was noted on his limbs and trunk. Lesions of the rash were red and a few mm in diameter. No organisms were isolated from several blood cultures. The child was treated with tetracycline and recovered. Serological tests of acute and convalescent serum samples from the child are most likely to reveal an increase in antibody titer to...

A.

Borrelia burgdorferi.

B.


C.


D.

Yersinia pestis.

E.

*Rickettsia rickettsii.

166.


A.


B.


C.


D.


E.


167.

A farmer comes to the ER with a 1-week history of flu-like symptoms with photophobia. His severe headache, cough, and myalgias suggest to the physician some kind of respiratory infection.

However, more careful physical exam reveals conjunctival suffusion and macular rash. Lab findings include elevated serum bilirubin, alkaline phosphatase, aminotransferase, and creatine phosphokinase.

With this clinical picture and lab results, the physician prescribes penicillin G immediately. His suspicions are confirmed later when a spirochete is isolated from the patient’s blood. Which of the

168.

following is the most likely cause?

A.

Treponema pallidum

B.

*Leptospira interrogans

C.


D.


E.

Treponema vincentii

Mycoplasma pneumoniae is a common cause of atypical pneumonia (walking pneumonia) and chest x-ray often looks worse than symptoms suggest. Which of the following groups of people is the most commonly affected?

A.

Elderly

B.

Middle-aged adults

C.

*School-age children

D.

Neonates

E.

Pregnant mothers

169.

A 10-year-old boy in Virginia presents with a rash, fever, and severe headache that began several days ago. The rash began on his palms and soles and has now spread to his trunk. His pediatrician also notes conjunctival redness, and lab studies show proteinuria. The boy’s history is significant for a hike in the woods a week ago. The child is given tetracycline and his diagnosis is confirmed by a Weil-Felix test. Which of the following is the most likely cause?

A.


B.

Coxiella burnetii

C.


D.


E.

Rickettsia acari

170.

A cattle farmer goes to the doctor complaining of mild cough and fever. He says that the fever began abruptly several days ago. His occupation as cattle slaughterer leads the doctor towards a diagnosis, and tetracycline is administered. The diagnosis is confirmed by serology and a negative Weil-

Felix test. Which of the following is the most likely cause?

A.


B.

*Coxiella burnetii

C.


D.


E.

Rickettsia sibirica

A Kosovo refugee sees a volunteer camp doctor complaining of a rash spreading outward from 171.

his trunk but sparing his palms and soles. Two days ago, he experiences abrupt onset of fever, headaches, and confusion. On physical exam, the doctor discovers lice in the man’s hair. The doctor treats with a delousing regimen and tetracycline. Were he at a hospital, he might confirm the diagnosis with a Weil-Felix test. Which of the following is the most likely cause?

A.


B.

Coxiella burnetii

C.


D.


E.

Bartonella quintana

172.


A.


B.


C.


D.


E.


173.


A.


B.


C.


D.


174.

E.

Nucleic acids


A.


B.


C.


D.


175.

E.



A.


B.

Innate and humoral.

C.


D.


176.

E.



A.


B.


C.


D.


E.


177.


A.


B.


C.


D.


178.

E.


A stool sample is plated on standard Endo-agar plates. After overnight incubation some of the colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the

179.

bacteria that produced dark-pink colonies?

A.

Gram-positive.

B.

*Ferment lactose.

C.


D.

Non-motile.

E.

Produce capsules.


A.


B.


C.


D.

Escherichia coli.

180.

E.



A.


B.


C.


D.


181.

E.


In the morning mss R. had become ill, with high fever, severe headache, and stiff neck. She was admitted to the hospital. Later that day she developed rash, at first petechial and then pupuric. Gram stain of CSF showed many white cells and Gram-negative cocci, many in pairs. Which organism is most likely to be the cause of her infection?

A.

Escherichia coli.

B.


C.


D.


E.


182.



A.


B.

Teichoic acid.

C.


D.


E.


183.

A patient has cellulitis of the left arm, persistent fever, and a heart murmur. He is a habitual user of illegal drugs, which he self-administers intravenously. An echocardiogram shows a bacterial vegetation on the aortic valve. Three blood cultures all grow an ?-hemolytic Gram-positive coccus,

184.

catalasenegative. Which organism is most likely to have caused his infection?

A.


B.


C.


D.


E.


Administration of which of the following vaccines would be contra-indicated in an patient with impaired cell-mediated immunity?

A.

Pneumococcal vaccine (pediatric).

B.

Pneumococcal vaccine (adult).

C.

*BCG vaccine against tuberculosis.

D.

Tetanus toxoid.

E.

Acellular Pertussis vaccine.

185.


A.

*Escherichia coli.

B.


C.


D.


E.


186.



A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

187.

E.

*Shigella.

A child develops a “cold” which progresses to severe pharyngitis. Pharyngeal exudate forms a tough ‘membrane’, difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which organism is most likely to have caused this infection?

A.


B.


C.

Candida albicans.

D.


188.

E.


A patient has rapidly spreading soft-tissue infection with gas in infected tissue. Fluid from a blister contains many large Gram-positive rods which grow on sheep blood agar anaerobically but not

189.

aerobically. Which pathogen is most consistent with these findings?

A.

Bacillus anthracis.

B.

Bacillus cereus.

C.


D.


E.


Untreated pharyngitis produced by Group A streptococci can result in later development of

Acute rheumatic fever, created by cross-reaction of anti-streptococcal antibodies with heart tissue.

Which streptococcal antigen stimulates formation of these cross-reactive antibodies?

A.

Group A carbohydrate.

B.

Flagella.

C.

*M protein

D.

Peptidoglycan.

E.

Teichoic acid.

190.

191.

A child is diagnosed with Pertussis. How was this infection most likely to have been acquired?

A.


B.


C.

Contact with livestock or animal products such as leather or wool.

D.

*Inhalation of respiratory droplets of another human being.

E.

Release of oral flora into the bloodstream by dental work


A.


B.

Basophils.

C.

Enterocytes.

D.

Erythrocytes.

E.

Neutrophils.

192.


A.


B.


C.


D.


193.

E.


A vacationer has “Traveler’s diarrhea” produced by enterotoxigenic E. coli. His profuse watery diarrhea is produced by a protein exotoxin secreted by this bacterium. Which statement below best

194.

describes the effect of this exotoxin?

A.


B.


C.


D.


E.


The severe diarrhea of cholera is produced by a protein exotoxin that acts on enterocytes. Which

195.

statement below best describes the effect of Cholera toxin?

A.


B.


C.


D.


E.



Streptococcus?

A.


B.

Bile-esculin test.

C.


D.


E.


196.


A.


B.


C.


D.


E.


DNA.

197.

A medical student with a three-week history of respiratory illness is treated with erythromycin [a

198.

macrolide]. Which phrase best describes the process inhibited by this drug?

A.

Transcription by bacterial RNA polymerase.

B.

Supercoiling of bacterial DNA.

C.

Cross-linking of peptidoglycan.

D.

Polymerization of peptidoglycan.

E.

*Peptide bond formation by bacterial ribosomes.


A.

M-proteins.

B.


C.


D.


E.


199.


A.


200.

B.

Gall bladder.

C.

Large intestine.

D.

*Nasopharynx.

E.



201.

202.


A.

A membrane-bounded inclusion body, within the nucleus.

B.

*A membrane-bounded inclusion body, within the cytoplasm.

C.


D.


E.


An infant is brought to the emergency room, cyanotic and with poor muscle tone.

Which condition is most likely given these findings?

A.


B.

Diphtheria.

203.

C.

Anthrax.

D.

*Botulism.

E.

Tetanus.

In what way do Haemophilus influenzae, Neisseria meningitidis, and Streptococcus pneumoniae most closely resemble each other?

A.

*Polysaccharide capsules.

B.

Lipopolysaccharide in their outer membranes.

C.

Teichoic acid in their envelopes.

D.

Thick peptidoglycan in their cell walls.

E.

Motility due to flagella.

204.


A.

Age over 70 years.

B.


C.

*Gallstones.

D.

Kidney stones.

E.


205.


A.


B.

*Tissue ischemia.

C.


D.


E.


206.

A patient develops pneumonia caused by Streptococcus pneumoniae. The predominant virulence factor of this organism is a thick capsule . Which phrase best describes the role of this capsule in

207.

virulence?

A.


B.


C.


D.


E.



A.


B.


C.

Escherichia coli.

D.


E.


208.

A 50-year-old woman was treated for cystitis [caused by E. coli] with an oral broad-spectrum antibiotic. Three weeks later she developed abdominal pain and diarrhea. A stained smear of stool contained many neutrophils. Cultures for bacterial pathogens were negative. A serological test of stool for Clostridium difficile toxin was positive. Which of the following is most likely to have been the immediately predisposing cause of this patient’s

G.

difficile infection?

A.


B.


C.


209.

D.


E.

All are true

A culture of skin lesions from a patient with pyoderma (impetigo) shows numerous colonies surrounded by a zone of beta hemolysis on a blood agar plate. A Gram-stained smear shows grampositive cocci. If you found the catalase test to be negative, which one of the following organisms would you MOST probably have isolated?

A.


B.


C.


D.


210.

E.

All are true

Five hours after eating fried rice at a restaurant, a 24-year-old woman and her husband both developed nausea, vomiting, and diarrhea. Which of the following organisms is the MOST likely to be

211.

involved?

A.


B.


C.

*Bacillus cereus

D.

Salmonella typhi

E.

All are true

Your patient is a 70-year-old man who underwent bowel surgery for colon cancer 3 days ago. He now has a fever and abdominal pain. You are concerned that he may have peritonitis. Which one of the following pairs of organisms is MOST likely to be the cause?

A.


B.


C.


D.


E.

All are true

212.

A 65-year-old man develops dysuria and hematuria. A Gram stain of a urine sample shows gram-negative rods. Culture of the urine on EMB agar reveals lactose-negative colonies without evidence of swarming motility. Which one of the following organisms is MOST likely to be the cause of

213.

his urinary tract infection?

A.

Enterococcusfaecalis

B.


C.

Proteus vulgaris

D.

Escherichia coli

E.

All are true

A 25-year-old man complains of a urethral discharge. You perform a Gram stain on a specimen of the discharge and see neutrophils but no bacteria. Of the organisms listed, the one MOST likely to cause the discharge is

A.

Treponema pallidum

B.


C.

Candida albicans

D.

Coxiella burnetii

E.

All are true

214.

Two hours after a delicious Thanksgiving dinner of barley soup, roast turkey, stuffing, sweet potato, green beans, cranberry sauce, and pumpkin pie topped with whipped cream, the Smith family of four experience vomiting and diarrhea. Which one of the following organisms is MOST likely to cause these symptoms?

A.

Shigella flexneri

B.


C.


D.


E.

All are true

A 35-year-old woman presents with a history of increasing respiratory distress and cough 215.

productive of sputum. Chest X-ray shows evidence of bilateral pneumonia. Cultures of blood and sputum on Chocolate agar grow out slender Gram-negative rods; cultures on standard sheep blood agar are negative. Which bacterium is most likely to be the cause of her infection?

A.


B.


C.


D.

Escherichia coli.

E.

Streptococcus pneumonia

216.


A.


B.


C.


D.


217.

E.



A.


B.


C.

Streptococcus mitis

D.


218.

E.



A.


B.


C.

Streptococcus mitis

D.


E.


219.


220.


A.


B.


C.

*Escherichia coli

D.


E.

Enterobacter, sp.


A.

Salmonella enterica

B.

*Escherichia coli

C.


D.


E.

Helicobacter pylori

221.

A child develops a "cold" which progresses to severe pharyngitis. Pharyngeal exudate forms a tough 'membrane', difficult to remove without causing bleeding. Culture of a throat swab on selective tellurite agar produces abundant black colonies. Other cultures produce only normal flora. Which

222.

organism below is most likely to have caused this infection?

A.


B.


C.


D.


E.


A burn patient develops infection of the burn wound. Culture of exudate on Brain-Heart Infusion agar produces numerous green-pigmented colonies of a Gram-negative rod. The organism grows well aerobically on standard media but shows no evidence of acid production on differential media such as

MacConkey, Hektoen Enteric, or Triple-Sugar-Iron agars.

223.


A.


B.


C.


D.

Mycoplasma hominis.

224.

E.

Treponema pallidum


A.


B.


C.


D.


E.


225.

A post-surgical patient develops fever and there is redness and swelling around the surgical incision. A day later pus begins to flow from the incision; Gram stain of pus shows large numbers of neutrophils and many Gram-positive cocci, some in clusters. The organism is beta-hemolytic on blood

226.

agar, and is coagulase- and catalase-positive. Which organism is most likely?

A.


B.


C.


D.


E.


A patient presented with upper back pain. MRI imaging demonstrated inflammation of the T8-

T9 vertebral bodies consistent with osteomyelitis. A bone marrow biopsy, when cultured, produced colonies of Gram-positive cocci.Colonies on Sheep blood agar were 3-4 mm in diameter, off-white and beta-hemolytic. Colonies on Brain-heart infusion (BHI) agar were 2-3 mm in diameter and golden-

227.

yellow. Catalase and coagulase tests were positive. What was the most likely pathogen?

A.


B.


C.


D.


E.

Streptococcus mitis

A 20-year-old women presents at a local clinic with fever and abdominal tenderness. She reports having had unprotected sexual intercourse a few weeks earlier. Gram-negative diplococci are seen in a

Gram stain of vaginal secretions; many of the bacteria are inside polymorphonuclear leukocytes. Which virulence factor is most important in aiding this bacterium to initiate infection?

A.


B.

*Adhesive pili.

C.


D.

Endotoxin.

E.

Flagella.

228.

A 23-year-old medical student had headache and fever one evening. By the next morning she had become very ill, with high fever, severe headache, and stiff neck. She was admitted to the hospital. Later that day she developed rash, first petechial and then pupuric. Her white count was 26,000/ull, with 80% neutrophils and 10% 'bands'. Gram stain ofCSF showed many white cells and numerous bacteria. If the pathogen is Neisseria meningitidis, how would you expect it to appear on Gram stain?

A.

Gram-positive cocci, many in pairs.

B.

Gram-positive cocci, many in clusters.

C.

Isolated Gram-positive cocci.

D.

*Gram-negative cocci, many in pairs.

E.

Gram-negative cocci, many in clusters.

229.


A.

Shigella sonnei.

B.


C.

Salmonella typhi.

D.


E.

*Escherichia coli.

230.


A.

Non-typhoidal Salmonella.

B.


C.


D.


231.

E.

Non-cholera Vibrio.

A sexually-active woman develops a urinary tract infection which ascends to the kidneys

(pyelonephritis). Blood culture yields a beta-hemolytic Gram-negative rod. In this situation, which

232.

pathogen below is most common?

A.


B.


C.


D.


E.

*Escherichia coli.

23-year-old woman comes to your office because, for 3 days, she has experienced burning with urination, increased frequency of urination, and a continual feeling that she needs to urinate. She does not have vaginal discharge, fever, or flank pain. Rapid 'dipstick' urine tests are consistent with uncomplicated cystitis. Culture of urine on standard media produces a lactose-fermenting Gram-

233.

negative rod. In situations such as this, what is the most likely pathogen?

A.


B.

*Escherichia coli

C.


D.

Proteus vulgaris

E.



A.


B.


C.


D.

Escherichia coli.

234.

E.



During the procedure a biopsy of the stomach epithelium is obtained.

235.

Which observation would suggest Helicobacter pylori as the cause of illness?

236.

A.


B.


C.


D.


E.


A child has Pertussis. How was this infection most likely to have been acquired?

A.

Release of oral flora into the bloodstream by dental work.

B.


C.

Contact with livestock, or animal products such as leather or wool.

D.


E.

*Inhalation of respiratory droplets from another person.

A patient is diagnosed with Clostridium difficile colitis. Which item would represent a known 237.

238.

risk factor for such infections?

A.


B.


C.


D.


E.


A 22-year-old develops an abscess in his peritoneum following rupture of his appendix. Gram stain of exudate from his foul-smelling abscess reveals numerous polymorphonuclear leukocytes, Grampositive cocci, Gram-positive rods, and Gram-negative rods. Aerobic culture of the exudate at 37oC on blood and MacConkey agar yields only Enterococci.Which of the bacteria below is most likely to be the

239.

Gram-negative rods seen in the stained smear?

A.


B.

Proteus mirabilis.

C.


D.


E.



A.


B.


C.


D.

Clostridium tetani.

240.

E.


A patient has endocarditis produced by an alpha-hemolytic Streptococcus. This usually reflects spread of normal flora to the bloodstream. From which site is this isolate most likely to have spread?

A.

Anterior nares.

B.

Facial skin.

C.


D.

Distal urethra.

241.

E.

*Oropharynx


A.

*Escherichia coli

B.


C.


D.


E.


242.

A nine years-old child develops high fever and stiff neck. A spinal tap is performed. A Gramstained smear of cerebrospinal fluid reveals many neutrophils and Gram-negative cocci that resemble paired kidney beans within leucocytes. Which organism below is most likely to have caused this infection?

243.

A.

Escherichia coli

B.


C.


D.


E.



A.


B.


C.


D.


E.

Escherichia coli

244.

245.


A.


B.


C.


D.


E.



246.


A.


B.


C.


D.


E.


A young man has a large pus-filled abscess on his upper arm but does not go to a doctor. Several days later he is brought to the Emergency Room with fever, hypotension, and multiple organ failure.

Which of the following is most likely to be responsible?

A.


B.


C.


D.


E.


247.


A.


B.


C.


D.


E.


248.

A patient with Cystic fibrosis develops pneumonia. A Gram-negative rod is cultured from her respiratory tract. On nutrient-poor media it grows well and secretes large amounts of bright green pigment. It produces acid from none of the sugars on which it was tested (including lactose and sucrose). Which organism below is most likely?

A.

Shigella sonnei

B.

Salmonella typhi

C.


D.

Escherichia coli

E.


249.


A.


B.


C.


D.


E.

Sexually-transmitted

250.


A.


B.


C.


D.


251.

E.



A.

Salmonella

B.

ETEC

C.

Shigella

252.

D.

Yersinia

E.

*Campylobacter


A.


B.

Escherichia coli.

C.


D.


E.


253.

lesion?

A 40-years-old patient has a peptic ulcer. Which organism is most likely to have created this

A.


B.


C.

Escherichia coli.

D.


254.

E.



A.

Rare hamburger.

B.

Dog or cat.

C.


D.


255.

E.

*Another child.


A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

256.


A.


B.


C.


D.


257.

E.




A.


B.

Balantidium coli.

C.


D.

D.Giardia lamblia.

258.

E.

*Shigella.



A.


B.

Balantidium coli.

C.


D.

Giardia lamblia.

E.

*Shigella.

259.


A.

oxidase activity.

B.


C.


D.


E.


260.


A.


B.


C.


D.


E.


261.

A laboratory got a sample from a patient with diarrhoea. Which of the following media is an enrichment medium for the isolation of Shigella?

A.


B.


C.


D.

Endo medium

E.

*Selenite F broth.

262.

A laboratory got a sample from a patient with diarrhoea. Cholera toxin resembles which of the following toxins?

A.


B.

Diphtheria toxin.

C.

Tetanus toxin.

D.


263.

E.




A.


B.


C.


D.


264.

E.



A.


B.


C.


D.


265.

E.



266.

A.


B.


C.

phagotyping

D.


E.




A.


B.


C.


D.


E.


267.


A.


B.


C.


D.

Vibrio cholerae

268.

E.

*Shigella sonnei


A.


B.

pink colonies

C.

black colonies

D.


269.

270.


A.


B.


C.

All are true

D.


E.


271.

E.



A.


B.


C.


D.

Escherichia coli.

E.


272.


A.

Escherichia coli.

B.


C.


D.


E.



A.

tetracycline

B.

toxoid

C.

vaccine

D.

antiserum injection

273.

E.



A.


B.


C.


D.


E.



274.


A.

Rare hamburger.

B.


C.

Dog or cat.

D.


E.

*Another child.

275.


A.

EHEC

B.

EPEC

C.

EAggEC

D.

ETEC

E.

*EIEC

276.


A.


B.


C.


D.


E.


277.

278.


A.

dogs

B.

cats

C.

swine

D.

chickens

E.

*humans


A.


B.


C.

serotherapy

D.

vaccination

E.


279.

A young woman got cholera. To determine to which species the infectious agent belongs, the microbiologist performs some tests on colonies cultured from stool samples. These tests include the

280.

following EXCEPT:

A.


B.


C.


D.


E.


Among the Sunday night patients at the Smithville emergency room were ten young adults suffering from severe diarrhea. All of these individuals would normally characterize themselves as being in good health. All reported eating at a local Dairy fair during the weekend. Of the following bacterial species the least likely to be responsible is

A.

Campylobacter fetus

B.

Shigella flexneri

C.


D.


281.

E.



A.


B.


C.


D.


E.


282.


A.

Proteus mirabilis

B.


C.

Vibrio cholerae

D.


283.

E.



A.

milk

B.

poultry

C.

chicken

D.

clams

284.

E.

*hamburger



285.


A.


B.


C.


D.


E.


Healthy adult travelers visiting Peru are cautioned against eating uncooked vegetables and

286.

unpeeled fruits, and against drinking unbottled water. However, they are already resistant to cholera because of:

A.


B.


C.


D.


E.



A.


B.

pink colonies

C.

black colonies

D.


E.


287.


A.

Salmonella

B.

Yersinia

C.

ETEC

D.

Shigella

E.

*Campylobacter

288.


A.


B.


C.


D.


E.


289.

are all


A.


B.

fermentative

C.


D.

pathogens

290.

E.



A.

V. parahaemolyticus

B.

V. alginolyticus

C.

V. vulnificus

D.

V. cholerae non 01

291.

E.

*V. fluvialis

23-year-old woman comes to your office because, for 3 days, she has experienced burning with urination, increased frequency of urination, and a continual feeling that she needs to urinate. She does not have vaginal discharge, fever, or flank pain. Rapid 'dipstick' urine tests are consistent with uncomplicated cystitis. Culture of urine on standard media produces a lactose-fermenting Gramnegative rod. In situations such as this, what is the most likely pathogen?

A.


B.


C.

Proteus vulgaris

D.


292.

E.

*Escherichia coli

A 20-year-old college student goes to the student health center because of dysuna, frequency, and urgency on urination for 24 hours. She has recently become sexually active. On urmalysis, many polymorphonuclear cells are seen. The most likely organism responsible for these symptoms and signs is

A.


B.


C.

Gardnerella vaginalis

D.

Lactobacillus species

E.

*Escherichia coli

293.

A 23-year-old woman has a history of recurrent urinary tract infections, including at least one episode of pyelonephritis. Blood typing shows the P blood group antigen. Which of the following is likely to be the primary cause of her infections7

A.

Escherichia coli that produce heat-stable toxin

B.

Escherichia coli with K1 (capsular type 1) antigen

C.

Escherichia coli O139 (lipopolysaccharide O antigen 139)

D.

Escherichia coli O157 H7 (lipopolysaccharide O antigen 157, flagellar antigen

294.

E.

*Escherichia coli with P-pili (fimbriae)

A 27 year-old woman is admitted to the hospital because of fever, with increasing anorexia, headache, weakness, and altered mental status of 2 days'duration. She works for an airline as a cabin attendant, flying between the Indian subconti nent and other places in Southeast Asia and the West

Coast of the USA. Ten days prior to admission she had a diarrheal illness that lasted for about 36 hours.

She has been constipated forthe last 3 days. Her temperature is 39 °C, heart rate 68/min, blood pressure

120/80 mm Hg, and respirations 18/mm. She knows who she is and where she is but does not know the date. She is picking at the bed clothes. Rose spots are seen on the trunk. The remainder of the physical examination is normal. Blood cultures are done and an intravenous line is placed. The most likely cause of her illness is

A.

Enterotoxigenic Escherichia coli (ETEC)

B.

Shigella sonnei

C.

Salmonella enterica subspecies enterica serotype Typhimunum (Salmonella Typhimurium)

D.

Enteroinvasive Escherichia coli (EIEC)

295.

E.

*Salmonella enterica subspecies enterica serotypeTyphi (SalmonellfaTyphi)

A 60-year old man was admitted to the hospital 2 weeks previously because of head trauma and other injuries that resulted from an automobile accident. A urinary tract catheter was inserted at admission and remains in place. The man develops a urinary tract infection with a gram negative bacillus. The probable cause of this patients infection is

A.


B.

Providenaa rettgeri

C.

Escherichia coli

D.

Morganella morgana

296.

E.

*Indeterminable without culture and identification testing

A common serotype of enterohemorrhagic E. coli is ::A common serotype of enterohemorrhagic

E. coli is O157:H7. To which bacterial structure does the "H7" correspond?

A.

Pili.

B.

Capsule.

C.

LPS core polysaccharide.

D.

Porins.

297.

E.

*Flagella.


A.


B.


C.


D.


E.

*Escherichia coli

298.


A.

Age over 70 years.

B.


C.

Kidney stones.

D.


E.

*Gallstones.

299.



A.


B.

Teichoic acid.

C.


D.


300.

E.



A.


B.


C.


D.


301.

E.


A seven-day-old child develops high fever and stiff neck. A spinal tap is performed. A Gramstained smear of cerebrospinal fluid reveals many neutrophils and short, thick, Gram-negative rods of uniform length. This microbes can ferment lactose.Which organism below is most likely to have caused this infection?

A.


B.


C.


D.


E.

*Escherichia coli

302.


A.


B.


C.


D.

Serratia marcescens

303.

E.

*Escherichia coli.

A specimen of thick, bloody sputum from a hospitalized 80-year-old patient with chronic obstructive pulmonary disease is sent for laboratory analyses. The tests yield heavy growth of a lactosepositive, nonmotile, gram-negative rod with a large gelatinous capsule. Which of the following is this bacterium most likely to be?

D.

coli

A.

Enterobacter aerogenes

B.

P. aeroginosa

C.

Y. pseudotuberoulosis

D.

*K. pneumoniae

304.

A stool sample is plated on standard Endo -agar plates. After overnight incubation some of the colonies are dark pink in color, others are pale, nearly colorless. What can you conclude about the bacteria that produced dark-pink colonies?

A.

Gram-positive.

B.


C.

Non-motile.

D.

Produce capsules

305.

E.

*Ferment lactose.


A.


B.

*Ferments lactose and produces gas

C.

Ferments sucrose and produces gas.

D.


E.


306.


A.

Salmonella enterica

B.


C.


D.

Helicobacter pylori

307.

E.

*Escherichia coli

A vacationer has “Traveler’s diarrhea” produced by enterotoxigenic E. coli. His profuse watery diarrhea is produced by a protein exotoxin secreted by this bacterium. Which statement below best describes the effect of this exotoxin?

A.


B.


C.


D.


E.


308.


A.

Shigella sonnei.

B.


C.

Salmonella typhi.

309.

D.


E.

*Escherichia coli.

A young woman develops urgency, frequency, and dysuria. Two days later she develops fever, chills, and costovertebral angle tenderness. Tests of urine for leukocyte esterase and nitrate reductase are

positive. Urine culture yields a beta-hemolytic Gram-negative rod which forms dark-pink colonies on


A.


B.


C.


D.

Enterobacter, sp

310.

E.

*Escherichia coli


A.


B.


C.


D.


E.


311.


A.


B.


C.


D.


312.

E.


After inoculation of the patient’s faces on Endo medium there were grown to types of colonies: one – red with metallic hue, other - colorless. To what group of nutrient media does Endo medium belong to?

A.

Elective

B.

Enriching media

C.

Universal

D.

Selective

E.

Differential diagnostic

313.

An old man has a urinary tract infection caused by E. coli. By what route are such infections most commonly acquired?

A.


B.


C.


D.

coli spreads from skin

E.


314.

An uncommon serotype of Salmonella enterica subspecies enterica was found by laboratories in the health departments of adjacent states. The isolates were all from a small geographic area on either side of the border between the states, suggesting a common source for the isolates (All the isolates were from otherwise healthy young adults who smoked marijuana the same salmo nella was isolated from a specimen of the marijuana). By what method did the laboratories determine that these isolates were the same?

A.

Capsular (K antigen) typing

B.

DNA sequencing

C.

Sugar fermentation pattern determination

D.

Decarboxylase reaction pattern determination

315.

E.

*O antigen and H antigen typing

Bacteriologists (using the Kauffman-White classifi::Bacteriologists (using the Kauffman-White classification) made conclusion that outbreak has been caused by Salmonella enterica, serotype

316.

Anatum. Structure of which pair of antigens determined the serotype as Anatum?

A.


B.


C.


D.


E.

*Flagella and O-antigen. from blood cultures of the patient a non lactose fermenting gram negative bacillus grows. Which of the following is likely to be a constituent of this organism?

317.

A.

antigen 157, H antigen 7 (0157 H7)

B.

antigen 139(0139)

C.

Urease

D.

K1 (capsular type l)

E.

*Vi antigen (capsule, virulence antigen)

During a vacation at a Caribbean resort, a 26-year-old executive develops profuse watery diarrhea. If his illness is produced by E. coli, which virulence factor of this organism is most likely to be responsible for the diarrhea?

A.

A conjugative plasmid that contains antibiotic-resistance transposons.

B.

A pathogenicity island which enables E. coli to invade mammalian cells.

C.

An iron-transport system more efficient than that present in non-pathogenic E. coli.

D.

A toxin that cleaves ribosomal RNA's.

E.

*A plasmid-borne gene which encodes a heat-stable peptide toxin that stimulates guanyl cyclase.

318.

Epidemiologists (using the Kauffman-White classification) report that an outbreak has been caused by Salmonella enterica, serotype Newport. Structure of which pair of antigens determined the serotype as Newport?

A.


B.


C.


D.

Hemolysin and cell-wall-associated carbohydrate

E.


319.

Microbiologists (using the Kauffman-White classification) report that an outbreak has been caused by Salmonella enterica, serotype Newport. Structure of which pair of antigens determined the serotype as Newport?

A.


B.


C.


D.


E.


320.

Several medical students go to Cancun over spring break. One evening, at a local bar, they drink several pitchers of Margaritas made with crushed ice. They spend the next two days in their hotel room with severe watery diarrhea, but no chills or fever. By the third day they recover completely. Which

321.

organism is most likely to have been the cause of their illness?

A.

Non-typhoidal Salmonella

B.


C.


D.

Non-cholera Vibrio.

E.


The main effect of E. coli and Vibrio cholerae enterotoxin on host cells of the gastrointestinal

322.

tract that leads to the pathology of the diseases, is to

A.


B.


C.


D.


E.


Water to be used for parenteral injection must sterilized to kill living microbes and then further

323.

purified to remove non-living bacterial components. Of those listed below, which is the most toxic?

A.


B.


C.


D.

Nucleic acids

E.


What color does acquire the semi-solid Hiss media with the rosolic acid as indicator when bacteria utilize sugar?

A.

*red

B.

green

C.

brown

D.

a color does not change

E.

dark blue

324.


He now has a fever and abdominal pain. You are concerned that he may have peritonitis. Which one of the following pairs of organisms is MOST likely to be the cause?

A.


B.


C.


D.


325.

E.


What is the main effect of E. coli and Vibrio cholerae enterotoxin on host cells of the gastrointestinal tract that leads to the pathology?

A.


B.


C.


D.


E.


Test’s questions to figures

1.

What does this figure show? Fig. 68

A.

*Reassortment of Influenza Viruses

B.

Antigenic drifts

C.

Partial variation of influenza virus

D.

Transformation between bird’s and human’s influenza viruses

E.

Transduction between bird’s and human’s influenza viruses

2.

What virus is in this figure? Fig. 69

A.

Herpes simlex virus 1

B.

Varicella-Zoster virus

C.

Picornavirus

D.

*Adenovirus

E.

Cytomegalovirus

3.

What virus is in this figure? Fig. 70

A.

Herpes simlex virus 1

B.

Varicella-Zoster virus

C.

Picornavirus

D.

Adenovirus

E.

*Bunyavirus

4.

Which type of the capsomers arrangement around the nucleic acid is shown in figure? Fig. 71

A.

Complex symmetry

B.

*Helical symmetry

C.

Icosahedral symmetry

D.

Irregular symmetry

E.

Polyhedron symmetry

5.

Which stage of the viral replication among listed is not unique for this virus? Fig. 72

A.

Adsorption

B.

DNA entry into cell

C.

*Uncoating

D.

Assembly

E.

Release

6.

Which from the following viruses has such a morphology and ultrastructure? Fig. 82

A.

Bunyavirus

B.

Orthomyxovirus

C.

Adenovirus

D.

*Picornavirus

E.

Parvovirus

7.

Which test mechanism is shown in this figure? Fig. 83

A.

Hemadsorption

B.

*Hemagglutination

C.

Agglutination

D.

Hemolysis

E.

Coagglutination

8.

What viral disease main reservoir do these animals comprise? Fig. 84

A.

Japanese encephalitis

B.

Yellow fever

C.

Herpetic keratoconjuctivitis

D.

*Hemorrhagic fever with kidney syndrom

E.

Fever, arthralgia

9.

What human virus can have such morphology? Fig. 85

A.

Mumps virus

B.

Herpes virus

C.

Poliovirus

D.

Rotavirus

E.

*Influenza virus

10.

Which viral disease is observed in a child? Fig. 86

A.

Mumps disease

B.

Measles

C.

*RSV-bronchopneumonia

D.

Rotaviruses enteritis

E.

Herpes simplex 1

11.

What viral diseases this symptom is pathognomic for? Fig. 87

A.

Mumps

B.

*Measles

C.

Influenza

D.

Varicella

E.

Herpes simplex 1

12.

What immunological test is shown in the figure? Fig. 88

A.

Hemadsorption

B.

*Hemagglutination inhibition test

C.

Agglutination

D.


E.

Coagglutination

13.

Which virus can cause this disease? Fig. 89

A.

Mumps virus

B.

Herpes virus

C.

*Poliovirus

D.

Rotavirus

E.

Influenza virus

14.

Which virus can cause this skin and mucosa lesion (vesicle)? Fig. 90

A.

Mumps virus

B.

Adenovirus

C.

*Herpes simplex 1

D.

Rotavirus

E.

Influenza virus

15.

What phenomenon is shown in this figure? Fig. 91

A.

Interaction between cells in the immune response

B.

Cytotoxic action of mammalian viruses on the host cells

C.

Lysogenic life cycle of the bacterial viruses

D.

*Lytic life cycle of the bacterial viruses

E.

Retroviruses replication

16.

What objects are represented in the figure? Fig. 92

A.

Artificial nutrience media

B.

Method of obtaining inactivated vaccine

C.

*Different tissue cell cultures

D.

Glass for virus cultivation

E.

Glass dishes for serological tests

17.

What does this man do? Fig. 93

A.

He dillutes patient’s serum

B.

He inoculates infected material into meat pepton broad

C.

*He works with tissue culture

D.

He examinates pH of nutrience medium

E.

He prepares viral specimens for electron microscopy

18.

What family does this virus belong to? Fig. 94

A.

Rhabdoviridae

B.

Picornaviridae

C.

*Paramyxoviridae

D.

Orthomyxoviridae

E.

Bunyaviridae

19.

What virus is in figure? Fig. 43

A.

HAV

B.

HBV

C.

*HCV

D.

HDV

E.

HEV

20.

What virus is in the figure? Fig. 44

A.

HAV

B.

HBV

C.

HCV

D.

*HDV

E.

HEV

21.


A.

HAV

B.

*HIV

C.

Herpesvirus

D.

Adenovirus

E.

HEV

22.


A.

*HAV

B.

HBV

C.

HCV

D.

HDV

E.

HEV

23.


A.

HEV

B.

HDV

C.

HCV

D.

*HBV

E.

HAV

24.

Replication cycle of what viruses is here in this figure? Fig. 47

A.

HAV

B.

Herpesvirus

C.

Adenovirus

D.

*HIV

E.

Poxvirus

25.

What structural element of HIV is marked in by letter A? Fig. 48

A.

*RNA

B.

DNA

C.

Reverse transcrtiptase

D.

p17 Matrix protein

E.

No correct answer

26.

What structural element of HIV is marked in by letter B? Fig. 48

A.


B.

p24 capsid protein

C.

Envelope (lipid membrane)

D.

gp120 envelope protein

E.

*gp41 envelope protein

27.

What structural element of HIV is marked in by letter C? Fig. 48

A.


B.

p24 capsid protein

C.


D.

*gp120 envelope protein

E.


28.

What structural element of HIV is marked in by letter D? Fig. 48

A.


B.

*p17 Matrix protein

C.


D.


E.


29.

What structural element of HIV is marked in by letter E? Fig. 48

A.


B.

p17 Matrix protein

C.

*Envelope (lipid membrane)

D.


E.


30.

What structural element of HIV is marked in by letter F? Fig. 48

A.


B.

p17 Matrix protein

C.


D.

*p24 capsid protein

E.


31.

What structural element of HIV is marked in by letter G? Fig. 48

A.

*Reverse transcrtiptase

B.

p17 Matrix protein

C.


D.

p24 capsid protein

E.


32.

There are clinical signs of what disease? Fig. 49

A.

Herpes infection

B.

Adenoviral infection

C.

*Kaposi’s sarcoma

D.

Small pox

E.

No correct answer

33.

What viruses are there in the figure? Fig. 50

A.

HBV

B.

HCV

C.

HDV

D.

*HIV

E.

Polioviruses

34.

What is there in the figure? Fig. 51

A.

Blood transfusion

B.

*Routes of AIDS transmission

C.

Rhesus conflict

D.

Drug injection

E.

No correct answer

35.


A.

Primary immune response in AIDS’ patient

B.

Secondary immune response in AIDS’ patient

C.

*Evolution of antibodies in AIDS’ patient

D.

Evolution of viral antigens in AIDS’ patient

E.

No correct answer

36.

What causative agents are there in the figure? Fig. 53

A.

Herpes virus

B.

Adenovirus

C.

*Pneumocystis carinii

D.

HIV

E.

HBV

37.


A.

Pneumocystis carinii

B.

*Histoplasma capsulatum

C.

Cryptosporidium

D.

Cryptococcus neoformans

E.

Aspergillus niger

38.


A.

Pneumocystis carinii

B.

Histoplasma capsulatum

C.

*Cryptosporidium

D.

Cryptococcus neoformans

E.

Aspergillus niger

39.

There are clinical signs of what disease? Fig. 56

A.

Herpes infection

B.


C.

Kaposi’s sarcoma

D.

Small pox

E.

*Candidiasis

40.

There are clinical signs of: Fig. 57

A.

Herpetic infection

B.


C.

Haemorrhagic fever

D.

Small pox

E.

*Kaposi’s sarcoma

41.

There are clinical signs of: Fig. 58

A.

Herpetic infection

B.


C.

Haemorrhagic fever

D.

*AIDS

E.

Kaposi’s sarcoma

42.

This test is used for diagnosis if AIDS. There is: Fig. 59

A.

Hemagglutination test

B.

Hemagglutination inhibition test

C.

Neutralization test

D.

*ELISA

E.

Western-blot test

43.

This test is used for diagnosis if AIDS. There is: Fig. 60

A.


B.


C.

Neutralization test

D.

ELISA

E.

*Western-blot test

44.

Replication cycle of what viruses is there in this figure? Fig. 61

A.

*HAV

B.

HBV

C.

HDV

D.

HIV

E.

HCV

45.


A.

*Typical Serologic Course of Acute Hepatitis A

B.

Typical Serologic Course of Chronic Hepatitis A

C.

Concentration of HAV in human body

D.


E.

No correct answer

46.

There is genome structure of: Fig. 63

A.

HAV

B.

*HBV

C.

HCV

D.

HDV

E.

HEV

47.

Select the chart of Adenovirus among the represented: Fig. 37

A.

*1

B.

2

C.

3

D.

4

E.

5

48.

Select the chart of Herpes simplex virus among the represented: Fig. 35

A.

*1

B.

2

C.

3

D.

4

E.

5

49.

Select the chart of Rabdovirus among the represented: Fig. 36

A.

1

B.

2

C.

3

D.

4

E.

*5

50.

Select the chart of Rotavirus among the represented: Fig. 37

A.

3

B.

*4

C.

5

D.

6

E.

7

51.

Select the chart of Coronavirus among the represented: Fig. 35

A.

1

B.

2

C.

3

D.

*4

E.

5

52.

Select the chart of Arenavirus among the represented: Fig. 35

A.

*7

B.

6

C.

5

D.

4

E.

3

53.

Select the chart of Bunyavirus among the represented: Fig. 35

A.

*2

B.

3

C.

4

D.

5

E.

6

54.

Select the chart of Togavirus among the represented: Fig. 36

A.

1

B.

*2

C.

3

D.

4

E.

5

55.

Select the chart of Flavivirus among the represented: Fig. 36

A.

1

B.

2

C.

3

D.

4

E.

*5

56.

What virus is shown on the figure: Fig. 34

A.


B.

Adenovirus

C.

Picornavirus

D.

*Bunyavirus

E.

Rabdovirus

57.


A.


B.

Adenovirus

C.

Picornavirus

D.

Bunyavirus

E.

*Rabdovirus

58.


A.

*Rabdovirus

B.


C.

Adenovirus

D.

Picornavirus

E.

Bunyavirus

59.


A.


B.

*Adenovirus

C.

Picornavirus

D.

Bunyavirus

E.

Rabdovirus

60.


A.

*Herpes simplex virus

B.

Adenovirus

C.

Picornavirus

D.

Bunyavirus

E.

Rabdovirus

61.

Which virus is carried by this insect? Fig. 27

A.

*Japanese encephalitis

B.

Omsk hemorrhagic fever

C.

Tick-borne encephalitis

D.

Influenza virus

E.

Crimea-Congo hemorrhagic fever

62.

Which virus is carried by the tick? Fig. 28

A.


B.

Dengue fever

C.

Yellow fever

D.

Influenza virus

E.

*Crimea-Congo hemorrhagic fever

63.

Which virus can cause such a disease? Fig. 29

A.


B.

*Rubella virus

C.

Yellow fever

D.

Influenza virus

E.

Crimea-Congo hemorrhagic fever

64.


A.

Influenza virus

B.

Rubella virus

C.

*Herpes simplex virus

D.

Adenovirus

E.

Picornavirus

65.


A.

Cytomegalovirus

B.


C.

*Herpes zoster

D.

Adenovirus

E.

Coxsackievirus

66.

Which virus can cause such a symptom of a disease? Fig. 32

A.

*Herpes zoster

B.

Cytomegalovirus

C.


D.

Adenovirus

E.

Coxsackievirus

67.

Which virus can cause the disease of this child? Fig. 33

A.

Cytomegalovirus

B.


C.

Adenovirus

D.

*Varicella zoster virus

E.

Coxsackievirus

68.

The 11 year old child has been hospitalized with the fever and rash which initially has occurred on the face and neck, and has spread to the trunk, arms extension surfaces, buttocks, hips the same day. What disease symptoms are these? Fig. 41

A.

Measles

B.

German measles

C.

*Rubella

D.

Chickenpox

E.

Typhus

69.

Which virus embryotoxic action causes congenital malformations such as cataract? Fig. 42

A.

Adenovirus

B.

Herpes zoster

C.

*Rubella virus

D.

Coronavirus

E.

Rotavirus

70.

The symptoms of shingles are depicted on the figure. What type of infection process does this disease belong? Fig. 31

A.

*Persistant infection

B.

Reinfection

C.

Superinfection

D.

Latent infection

E.

Mixed infection

71.

Which disease symptoms are performed on the figure? Fig. 39

A.

Candidiasis

B.

*Herpes infection

C.

Avitaminosis

D.

Periodontosis

E.

Dysbacteriosis

72.

What virus causes gingivostomatitis? Fig. 30

A.

*Herpes simplex virus type 1

B.

Herpes simplex virus type 2

C.

Varicella zoster virus

D.

Epstain-Bar virus

E.

Cytomegalovirus

73.

The child’s symptoms are: swollen peripheral lymph nodes, fever, malaise, tonsillitis. The previous diagnosis is infectious mononucleosis. What kind of virus does it cause? Fig. 38

A.


B.


C.


D.

*Epstain-Bar virus

E.

Cytomegalovirus

74.

The child’s inspection reveals the fever of 38C, papular-vesicular rash on the skin and mucous membranes. Which disease do they belong? Fig. 40

A.

Measles

B.

Rubella

C.

*Chickenpox

D.

Shingles

E.

German measles

75.

A 3 month old child has symptoms of the cataract. Neither traumas nor diseases took place after the child birth. During the pregnancy the mother contracted an acute virus disease. What virus might cause fetal malformations? Fig. 42

A.


B.

Morbilli virus

C.

Rubula virus

D.

*Rubella virus

E.

Epstain-Bar virus

76.

This rash is typical for: Fig. 78

A.

Streptococcal impetigo

B.

*Herpes simplex

C.

Chickenpox

D.

Smallpox

E.

Infectious mononucleosis

77.

Which disease pathogenesis is represented on the chart? Fig. 79

A.

Chickenpox

B.

Shingles

C.

*Herpes simplex

D.


E.

Cytomegalic inclusion disease

78.

Patient K. has the following symptoms: fever, intoxication, papular rash on the whole body. What diagnosis is suspected? Fig. 73

A.

Measles

B.

Chickenpox

C.

Allergic dermatitis

D.

*Rubella

E.


79.

Patient’s symptoms are fever, papular rash covering the body and face, intoxication. What previous diagnosis is the most appropriate? Fig. 74

A.

*Rubella

B.


C.

Allergic dermatitis

D.

Chickenpox

E.

Measles

80.

The chart represents the pathogenesis of a certain virus disease. Select one among all: Fig. 80

A.

Rubella

B.

Herpes simplex

C.

*Shingles

D.


E.


81.

The 3 year old child symptoms are: fever, intoxication, maculopapular rash on the face, trunk and extremities, redness of the pharynx mucous membranes. What previous diagnosis is the most appropriate? Fig. 81

A.

Measles

B.

Chickenpox

C.


D.

*Rubella

E.


82.

What virus can cause such a rush? Fig. 76

A.

Variola virus

B.


C.


D.

Cytomegalovirus

83.

The rash on the photo is typical for: Fig.76

A.

Smallpox

B.

Chickenpox

C.

Herpes simplex

D.

*Shingles

E.


84.

Which disease pathogenesis is represented on the chart? Fig.77

A.


B.

Measles

C.

Epidemic parotitis

D.

*Herpes simplex

E.

Chickenpox

85.

Which disease symptoms can be found in a child? Fig.67

A.

Measles

B.

*Rubella

C.

Chickenpox

D.


E.

Hives

86.

What agent can cause such a rash? Fig.75

A.

Herpes simplex

B.


C.

Cytomegalovirus

D.

Streptococcus

E.

Variola virus

87.

What is the expected diagnosis? Fig.75

A.

Measles

B.

Rubella

C.


D.

Chickenpox

E.

*Shingles

88.

Which virus model is represented in the figure? Fig.69

A.


B.

*Adenovirus

C.

Togavirus

D.

Bunyavirus

E.

Flavivirus

89.

What test is there in the figure? Fig. 5

A.

CFT

B.


C.


D.

ELISA

E.

*Indirect Hemagglutination test

90.

For what purpose was this test used? Fig. 5

A.

Detection of unknown antigen

B.

Identification of viruses

C.

*Detection the level of antiviral antibodies in patient’s serum

D.

Detection the level of immunoglobulines

E.

Examination the level of incomplete antibodies

91.

What component of indirect Hemagglutination test is marked by number 1in? Fig. 5

A.

Antigen

B.

*Patient’s serum

C.

Complement

D.

Immunoglobulin

E.

Red blood cell coated with antigen

92.

What component of indirect Hemagglutination test is marked by number 2 in? Fig. 5

A.

Antigen

B.

Patient’s serum

C.

Complement

D.

Immunoglobulin

E.

*Red blood cell coated with antigen

93.

What is the result marked by number 3 of this test in? Fig. 5

A.

Precipitation

B.

Agglutination

C.

*Hemagglutination

D.

Coagglutination

E.

Latex-agglutination

94.


A.

CFT

B.

*Hemagglutination test

C.


D.

ELISA

E.

Indirect Hemagglutination test

95.

What does this test help to examine? Fig. 6

A.

*presence of viruses

B.

identification of viruses

C.

ability to cause red cells’ lysis

D.

presence of antibodies in patience’s serum

E.

No correct answer

96.

What is the positive result of this test in? Fig. 6

A.

Precipitation

B.

Agglutination

C.

*Hemagglutination

D.

Coagglutination

E.

Latex-agglutination

97.


A.

CFT

B.


C.

*Hemagglutination inhibition test

D.

ELISA

E.


98.

What is the positive result of this test in? Fig. 7

A.

Precipitation

B.

Agglutination

C.

Hemagglutination

D.

Coagglutination

E.

*Agglutination of red blood cells absent

99.


A.


B.

Identification of viruses

C.

*Detection the level of antiviral antibodies in patient’s serum

100.

D.


E.



A.


B.

*Identification of viruses

C.

Detection the level of antiviral antibodies in patient’s serum

D.


101.

102.

103.

104.

105.

106.

107.

108.

109.

110.

E.


What stage of replication of virus is marked by number 1? Fig. 14

A.

Uncoating

B.

*Adsorption

C.

Entry

D.

Assembly

E.

Release


A.

Uncoating

B.

Adsorption

C.

*Entry

D.

Assembly

E.

Release


A.

Uncoating

B.

Adsorption

C.

Entry

D.

*Assembly

E.

Release

What stage of replication of viruse is marked by number 5? Fig. 14

A.

*Uncoating

B.

Adsorption

C.

Entry

D.

Assembly

E.

Release

What stage of replication of viruse is marked by number 6? Fig. 14

A.

Uncoating

B.

Adsorption

C.

Entry

D.

Assembly

E.

*Release

What method of inoculation of viruses into chicken embryo is marked by number 1? Fig. 14

A.

Allantoic inoculation

B.

*Amniotic inoculation

C.

Chorionallantoic membrane inoculation

D.

Yolk sac inoculation

E.

Albumen inoculation


A.


B.

Amniotic inoculation

C.

*Chorionallantoic membrane inoculation

D.


E.

Albumen inoculation


A.


B.


C.


D.

*Yolk sac inoculation

E.

Albumen inoculation


A.

*Allantoic inoculation

B.


C.


D.


E.

Albumen inoculation

What structure of virus is marked by number 1? Fig. 17

A.

Envelope

111.

112.

113.

114.

115.

116.

117.

118.

119.

B.

Capsid

C.

Nucleic acid

D.

Peplomer

E.

*Capsomer


A.

Envelope

B.

Capsid

C.

*Nucleic acid

D.

Peplomer

E.

Capsomer


A.

Envelope

B.

*Capsid

C.

Nucleic acid

D.

Peplomer

E.

Capsomer


A.

*Envelope

B.

Capsid

C.

Nucleic acid

D.

Peplomer

E.

Capsomer


A.

Envelope

B.

*Capsid

C.

Nucleic acid

D.

Peplomer

E.

Capsomer


A.

Envelope

B.

Capsid

C.

*Nucleic acid

D.

Peplomer

E.

Capsomer

What structure of bacteriophage is marked by number 1? Fig. 16

A.

Tail

B.

Contractile sheath

C.

*Head

D.

Base plate

E.

Tail fibres


A.

*Tail

B.

Contractile sheath

C.

Head

D.

Base plate

E.

Tail fibres


A.

Tail

B.

*Contractile sheath

C.

Head

D.

Base plate

E.

Tail fibres


A.

Tail

B.

Contractile sheath

C.

Head

D.

*Base plate

120.

121.

122.

123.

124.

E.

Tail fibres


A.

Tail

B.

Contractile sheath

C.

Head

D.

Base plate

E.

*Tail fibres


A.

Agglutination

B.

*Hemagglutination

C.

Coagglutination

D.

Latex-agglutination

E.

Precipitation


A.

Western blot

B.

Indirect fluorescent-antibody test

C.

Hemagglutination ingibition test

D.

*Hemagglutination test

E.



A.


B.

*Hemadsorption test

C.

Cytopathic effect

D.

Syncytium formation

E.

Inclusion bodies


A.


B.

Hemadsorption test

C.

Cytopathic effect

D.

Syncytium formation

E.

*Inclusion (Negri bodies)

Special, clinical and ecological microbiology.doc

Related documents

Products

Support

Special, clinical and ecological microbiology.doc

Related documents

Add this document to collection(s)

Add this document to saved

Suggest us how to improve StudyLib