Aerobic Gram-Positive Cocci Assessment
1.
What type of hemolysis on blood agar is described as complete clearing of blood around a
colony?
a.
Alpha
b.
Beta
c.
Gamma
d.
Alpha-prime
2.
Growth on media and colony morphology:
BAP - Abundant small, white, glistening, opaque, entire, raised and buttery
colonies; non-hemolytic
Mac - No growth
Gram stain - G+ cocci in cluster
Of the organisms listed, which is the most probable?
a.
b.
c.
d.
S. epidermidis
S. aureus
E. coli
There is no way to determine the possible identification with the information
provided.
3.
Which of the following are NOT characteristic of Staphylococcus species?
a.
Catalase positive
b.
Gram positive
c.
Appear singly, in pairs and in clusters
d.
Lactose positive
4.
A multisystem infection caused by S. aureus characterized by high fever, hypotension,
and shock that has been associated with the use of tampons is:
a.
Scalded skin syndrome (SSS)
b.
Impetigo
c.
Toxic shock syndrome (TSS)
d.
Topic epidermal necrosis
5.
The main type of infection caused by S. epidermidis is:
a.
Impetigo
b.
Osteomyelitis
c.
Hospital acquired infection resulting from instrumentation procedures, such as
catheterization
6.
Pathogenicity of S. epidermidis is increased by the organism=s ability to produce:
a.
Slime
b.
Lipid A
c.
Capsule
d.
Acid-fast properties
7.
The main type of infection caused by S. saprophyticus is:
a.
Osteomyelitis
b.
Urinary tract infections in young, sexually active females
c.
Endocarditis
d.
Food poisoning
8.
What is the NEXT test that should be performed to identify this organism?
BAP - Abundant white, entire, glistening, raised, opaque, buttery colonies
MAC - No growth
Gram stain - G+ cocci in clusters
a.
Wet prep
b.
Catalase
c.
Coagulase
d.
Novobiocin susceptibility
9.
S. saprophyticus can be differentiated from other coagulast-negative staphylococci by
what test?
a.
Catalase
b.
Wet prep
c.
Coagulase
d.
Novobiocin susceptibility
10.
The serious resistant strain of S. aureus that is becoming commonly seen in such places as
high school gym classes is:
a.
MRSA
b.
MRSE
c.
VRSA
d.
VRSE
11.
Match the following organisms with the correct Lancefield grouping:
1. Streptococcus pyogenes
a. Group A
2. Enterococcus faecalis
b. Group B
3. Streptococcus pneumoniae
c. Group D
4. Streptococcus agalactiae
d. Does not possess Lancefield antigens
12.
Which of the following is strongly beta hemolytic?
a.
Group A
b.
Enterococcus
c.
Streptococcus pneumoniae
d.
viridans streptococcus
13.
A throat culture is ordered on a 9 year-old boy who has fever and sore throat over a 3 day
period. The culture has the following results:
Abundant beta hemolytic colonies on BAP which are resistant to bacitracin. What
is the most probable organism?
a.
Group A strep
b.
Group C strep
c.
Group D strep
d.
Based on these results, the organism cannot be identified.
14.
A sputum culture is ordered on an elderly patient with symptoms consistent with
pneumoniae. Alpha-hemolytic colonies that are sensitive to optochin are found in the
culture. The infecting organism is:
a.
Group A strep
b.
Group B strep
c.
Streptococcus pneumoniae
d.
viridans streptococcus
15.
A wound culture after 24 hour incubation produces tiny beta-hemolytic colonies on BAP.
Gram stain reveals them to be G+ cocci in pairs, clusters and chains. The NEXT step in
identifying this organism is:
a.
Bacitracin sensitivity
b.
Bile esculin hydrolysis
c.
Coagulase
d.
Catalase
16.
A surgical wound infection has produced G+ cocci on BAP. The colonies are small,
light grey, semi-opaque, and non-hemolytic. Catalase is negative. What is the next test
that should be performed to identify this organism?
a.
Bacitracin sensitivity
b.
Optochin sensitivity
c.
Bile esculin or PYR
d.
Repeat the catalase, as it should not be negative
17.
You suspect this urine is growing Group D Enterococcus. You have performed a bile
esulin test and get blackening on the bile esculin slant. To confirm this organism is
Group D Enterococcus, what test should be performed next?
a.
6.5% salt tolerance
b.
Bacitracin sensitivity
c.
Optochin sensitivity
d.
Blackening on the bile esculin slant does not indicate that this organism is
Enterococcus
18.
Timmy Jo=s mother brings him to the pediatrician with a sore throat and fever. The
pediatrician suspects strep throat and collects a swab for a rapid strep test, which is
negative for strep. What should the pediatrician do?
a.
Assume the rapid strep test results are incorrect and go ahead and put Timmy Jo
on antibiotics
b.
Assume the rapid strep test results are correct and do NOT prescribe antibiotics
for Timmy Jo
c.
Collect another swab and repeat the rapid strep test
d.
Collect another swab for a throat culture
19.
Which of the following best describes Group B strep?
a.
Non-hemolytic, optochin sensitive
b.
Hemolytic, CAMP test positive
c.
Hemolytic, PYR positive
d.
Non-hemolytic, bacitracin sensitive, optochin resistant
20.
If untreated or poorly treated, what are the sequelae resulting from streptococcal
pharyngitis?
a.
Rheumatic fever
b.
Acute glomerulonephitis
c.
Impetigo
d.
a and b