Pseudomonas aeruginosa

Question 1

what is the gram stain morphology of P. aeruginosa?

Answer 1

GNR

Question 2

Is P. aeruginosa fastidious?

Answer 2

not fastidious

Question 3

what are the oxygen growth requirements for P. aeruginosa?

Answer 3

anaerobic

NO3 is TEA

Question 4

is P. aeruginosa capable of fermentation?

Answer 4

non-fermenter

Question 5

what is the oxidase status of P. aeruginosa?

Answer 5

oxidase positive

Question 6

what pigments does P. aeruginosa produce?

Answer 6

Pyocyanin/1-hydroxyphenazine (1-hp): blue-green

Pyoverden (Fluorescin): yellow, UV enhanced

Question 7

what is the significance of Pyoverden production by P. aeruginosa?

Answer 7

physician can use wood’s lamp to check out burns for colonies

Question 8

besides pigments, what are the key virulence factors of P. aeruginosa?

Answer 8

exotoxin A: ADP-ribosyltransferase (EF-2 inact.)
degredative enzymes
mucoid exopolysaccharide/slime layer
quorum sensing

Question 9

what degradative enzymes are produced by P. aeruginosa?

Answer 9

proteases

elastase and alkaline protease

Question 10

where does the mucoid exopolysaccharide/slime layer of P. aeruginosa occur and what is it’s significance?

Answer 10

• occurs in bronchial tree of cystic fibrosis pts

- biofilm production

Question 11

what is the significance of quorum sensing in P. aeruginosa?

Answer 11

signals:

exotoxin production
biofilm formation

chronic infections

Question 12

is P. aeruginosa a common agent of pneumonia?

Answer 12

no, uncommon

Question 13

where does P. aeruginosa rank in mortality rate among all etiologic agents of pneumonia?

Answer 13

highest mortality rate

Question 14

what is the natural habitat/reservoir of P. aeruginosa/

Answer 14

ubiquitous/everywhere

NMF

Question 15

what is a common mode of transmission of P. aeruginosa in hospitals?

Answer 15

non-sterile water

Question 16

what are key risk factors for P. aeruginosa?

Answer 16

cystic fibrosis
neutropenia
burn patients

Question 17

is P. aeruginosa an opportunistic or frank pathogen?

Answer 17

opportunistic

Question 18

what type of pneumonia does P. aeruginosa result in?

Answer 18

consolidation pneumonia

Question 19

what is the disease course/speed in P. aeruginosa infx?

Answer 19

rapid progress

fulminant course w/ high mortality

Question 20

diagnosis buzz words for P. aeruginosa (in relation to sputum and cultures)

Answer 20

blue-green sputum
fruity smelling sputum
blue-green blood cultures
fruity smelling burn sites

Question 21

what are two common causes of MDR in P. aeruginosa?

Answer 21

• limited OM permeability

- Abx extrusion (efflux pump)

Question 22

to what drugs is Ceftazidime-resistant P. aeruginosa (MDR-PA) resistant?

Answer 22

ceftazidime, cefeprime (cephalosporins)
ciprofloxacin (fluoroquinolone)
imipenem
piperacillin

Question 23

what is the treatment for MDR-PA?

Answer 23

aminoglycosides (tobramycin) plus penicillin

Question 24

should the P. aeruginosa patient be isolated?

Answer 24

yes, respiratory isolation

Question 25

what other diseases are caused by P. aeruginosa?

Answer 25

PSEUDOmonas mnemonic

Pneumonia
Sepsis
External Otitis
UTI
Drug use
Osteomyelitis (diabetic)

Question 26

what are two words pretty much guaranteed to give away a P. aeruginosa diagnosis?

Answer 26

burn

CF