Pseudomonas aeruginosa Flashcards
what is the gram stain morphology of P. aeruginosa?
GNR
Is P. aeruginosa fastidious?
not fastidious
what are the oxygen growth requirements for P. aeruginosa?
anaerobic
NO3 is TEA
is P. aeruginosa capable of fermentation?
non-fermenter
what is the oxidase status of P. aeruginosa?
oxidase positive
what pigments does P. aeruginosa produce?
Pyocyanin/1-hydroxyphenazine (1-hp): blue-green
Pyoverden (Fluorescin): yellow, UV enhanced
what is the significance of Pyoverden production by P. aeruginosa?
physician can use wood’s lamp to check out burns for colonies
besides pigments, what are the key virulence factors of P. aeruginosa?
exotoxin A: ADP-ribosyltransferase (EF-2 inact.)
degredative enzymes
mucoid exopolysaccharide/slime layer
quorum sensing
what degradative enzymes are produced by P. aeruginosa?
proteases
elastase and alkaline protease
where does the mucoid exopolysaccharide/slime layer of P. aeruginosa occur and what is it’s significance?
- occurs in bronchial tree of cystic fibrosis pts
- biofilm production
what is the significance of quorum sensing in P. aeruginosa?
signals:
exotoxin production
biofilm formation
chronic infections
is P. aeruginosa a common agent of pneumonia?
no, uncommon
where does P. aeruginosa rank in mortality rate among all etiologic agents of pneumonia?
highest mortality rate
what is the natural habitat/reservoir of P. aeruginosa/
ubiquitous/everywhere
NMF
what is a common mode of transmission of P. aeruginosa in hospitals?
non-sterile water
what are key risk factors for P. aeruginosa?
cystic fibrosis
neutropenia
burn patients
is P. aeruginosa an opportunistic or frank pathogen?
opportunistic
what type of pneumonia does P. aeruginosa result in?
consolidation pneumonia
what is the disease course/speed in P. aeruginosa infx?
rapid progress
fulminant course w/ high mortality
diagnosis buzz words for P. aeruginosa (in relation to sputum and cultures)
blue-green sputum
fruity smelling sputum
blue-green blood cultures
fruity smelling burn sites
what are two common causes of MDR in P. aeruginosa?
- limited OM permeability
- Abx extrusion (efflux pump)
to what drugs is Ceftazidime-resistant P. aeruginosa (MDR-PA) resistant?
ceftazidime, cefeprime (cephalosporins)
ciprofloxacin (fluoroquinolone)
imipenem
piperacillin
what is the treatment for MDR-PA?
aminoglycosides (tobramycin) plus penicillin
should the P. aeruginosa patient be isolated?
yes, respiratory isolation
