Pseudomonas & Other Non

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Pseudomonas
&
Other Non-fermenters
Professor Sudheer Kher
KEY WORDS
• Pseudomonas
aeruginosa
• Pigments
– Pyocyanin
– Fluorescein
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Toxin A
Opportunistic Infections
Greenish Pus
Non-fermenter
Oxidase positive
Motile
Hospital infection
Antibiotic resistance
Pseudomonas
• Obligate Aerobe, mostly
saprophytic
• Gram-negative non-sporing rods
• Motile
• Majority of human infections
–P. aeruginosa
Medically important species of
Pseudomonas
Pigment
production
Greenish yellow
pigment
Pseudomonas aeruginosa
No pigment
Burkholderia mallei
Burkholderia pseudomallei
Common in the environment
• water
• air
• soil
P. aeruginosa and compromised host
• Burns and wounds
– destruction of blood vessels
– phagocyte access limited
•Cancer
– cytotoxic drugs
*destroy the immune system
•Cystic fibrosis
– altered respiratory epithelium
– pneumonia
Cystic fibrosis (CF) is a hereditary disease that affects mainly the lungs and digestive system, causing
progressive disability, and, for some, early death. Formerly known as cystic fibrosis of the pancreas, this entity
has increasingly been labeled simply cystic fibrosis.[1] Average life expectancy is around 37 years, although
improvements in treatments mean a baby born today could expect to live longer.[2]
.
Identification
• Pigments
– Pyocyanin (blue-green)
– Fluorescein (green-yellow, fluorescent)
– Best produced in King’s A & B Media
• Biochemical reactions – Non fermenter
•Oxidase positive
• Cultures have fruity smell (Grape like)
Pathogenesis
• Toxin A - ADP ribosylates
EF2
functions as NADase
– similar to diphtheria toxin
• Slime layer is anti-phagocytic
Virulence factors of P. aeruginosa
• Lipopolysaccharide: endotoxin, pyrogen
• Capsule: anti-phagocytosis, inhibits complement
fnc.
• Proteases: damage host proteins such as
complement and IgA
• Hemolysins
• Exotoxin A: a diptheria-like toxin - toxic for
macrophages
• Pyocyanin: impairs ciliary activity
• Fimbriae: adherence factor
• Other non-pilus adhesins
• Others like elastases………..
Pathogenesis
Source
Endogenous (skin of axilla, perineum or GIT)
Exogenous
Respirators, bed pans, lotions, ointments, eye
drops, stock of distilled water, disinfectants (QAC)
Transmission
Endogenous infection
Virulence
Toxin and Extracellular products
Contact spread
Protease , Pyocyanin, Cytotoxin (leukocidin)
Endotoxin, Haemolysin, Exotoxin A & Exotoxin S
Mucoid strains in Cystic fibrosis due to alginate
Diseases (Pathogenicity)
Community
Suppurative Otitis
Hospital
Nosocomial infection
Eye
Keratitis and Endophthalmitis
Ear
Otitis externa and Otitis media
Skin
Burns infection, wound sepsis
Ecthyma gangrenosum
UTI
Cystitis (catheterized)
RTI
Pneumonia (ventilation / tracheostomy)
GIT
Infantile diarrhea
CNS
Meningitis brain abscess (iatrogenic)
Lab Diagnosis
Specimens
Wound discharge, sputum, urine, blood
Microscopy
Gram negative bacilli
MAC
NLF, blue green with distinct feathered edges
NA
Green diffusible pigment
Cetrimide agar
Selective media
Identification tests
Oxidase + TSI: K- / K- (non fermenter)
Ceftazidime, ticarcillin, piperacillin, ciprofloxacin,
amikacin, gentamicin, Polymyxin B
Bacteriophage typing Hospital outbreak investigation
AST
Aeroginocine
(Pyocine) typing
11 Indicator strains
Phage Typing
Treatment & Control
Antipseudomonad beta lactam
Aminoglycosides
Fluoroquinolones
Combination therapy in impaired
defense mechanism
Strict attention to asepsis
Treatment of underlying disease
(correction of granulocytopenia)
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8:10 PM Atul: are you there
me: Hi
Atul: hi
8:11 PM me: That day I came on line in d evening but by that
time u were off! How's life?
Atul: did i tell you about isolation of burkholderia pseudomallei
at dharwad me: Saw my mail?
8:12 PM Atul: yha me: No. Just now I am preparing my power
point on that very topic. May be I can use ur story to make
lecture interesting!
8:13 PM Atul: please send me as many full text articles you can
on this topic.\ sure i will send you the case report. when do
you want it
8:14 PM me: Certainly. Can u send me a brief summary. May be
tomorrow a real brief one.. but incl all essentials.
Atul: sending it now
8:15 PM me: Wonderful. The students will like it and I will
mention the co-incidence that my friend was talking of exactly
the same organism!! Telepathy?
Burkholderia pseudomalai septicaemia – a case report
• A 35 old male working as daily labourer presented to the
Medicine OPD on 19th September 2007 at 1 pm with
complaint of fever for 8 days and reduced urine output
for about one month. He was known diabetic and was on
regular insulin therapy of which precise duration could
not be known. He belonged to the costal town Karwar of
Karnataka, India.
• On examination the patient was emaciated and
dehydrated. His blood pressure was 70 mm / 50 mm of
Hg and pulse rate was 120 per minute. CVS examination
revealed S1 S2. On auscultation he showed bilateral
basal crepitations. There was a vertical scar on the
abdomen and the patient gave history of splenectomy 10
years ago of which reason was not identified. Liver was
palpable one finger below costal margin and he had mild
ascitis. Samples were sent for investigation including
blood culture and he was put on Metrogyl (Dose) and
Monocef 1 gm i/v.
Burkholderia pseudo mallei
Whitmore’s bacillus
No pigment, motile
Cause Melioidosis (glanders like disease)
Acute septicemia (typhoid like disease)
Multiple abscess formation
Burkholderia mallei
Transmitted via rats either by rat fleas
or food contaminated with excreta
No pigment, non motile
Cause Glanders in horses, donkeys and mules
Rarely cause human disease (suppurative lesions)
Stenotrophomonas maltophilia (cont.)
EPIDEMIOLOGY
 Hospital Epidemics from Contaminated Moist
Reservoirs:
 Disinfectant solutions
 Respiratory equipment
 Ice machines
 Flower vases
 Risk Factors
 Hospitalization
 Impaired host defense mechanisms (e.g., highly
immunocompromised)
 Long-term broad-spectrum antibiotics (e.g., bone
marrow transplant patients)
Acinetobacter baumanii (calcoaceticus)
CLINICAL SYNDROMES
Opportunistic Infections
 Respiratory tract
 Urinary tract
 Wounds
 Septicemia
EPIDEMIOLOGY
 Niches Include:
 Natural environments
 Moist surfaces in hospitals (e.g., respiratory therapy
equipment)
 Dry surfaces (e.g., human skin); rare for gram-negative bacilli
 Occasionally normal flora in oropharynx
TREATMENT, PREVENTION & CONTROL
 Antibiotic Resistance Common
 Empirical Treatment for Acute Infections: β-lactam +
Aminoglycoside
 Specific Therapy According to Antibiotic Susceptibility
Moraxella catarrhalis
GENERAL OVERVIEW
 Formerly classified as Neisseria & more recently Branhamella
CLINICAL SYNDROMES
 In Elderly Patients with Chronic Pulmonary Disease
 Bronchitis
 Bronchopneumonia
 In Previously Healthy People
 Sinusitis
 Otitis
TREATMENT, PREVENTION, AND CONTROL
 Most strains produce β-lactamase; Penicillin Resistant
KEY WORDS
• Pseudomonas
aeruginosa
• Pigments
– Pyocyanin
– Fluorescein
•
•
•
•
•
•
•
•
Toxin A
Opportunistic Infections
Greenish Pus
Non-fermenter
Oxidase positive
Motile
Hospital infection
Antibiotic resistance
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