Pseudomonas

Question 1

Pseudomonas species

Answer 1

Pseudomonas aureginosa

Question 2

Pseudomonas general characteristics

Answer 2

Gram negative rod
aerobic
motile by polar flagella
Non-lactose fermenting**
Oxidase positive **
Characteristic sweet grape like odor**
primary opportunistic, nosocomial infection

Question 3

Where does Pseudomonas live

Answer 3

Everywhere
environment: soil, water, warm, cold blooded animals, flowers, fruits, veggies
sometime normal flora (less than 10% of people)- stool, skin, throat, nasal mucosa
throughout hospital environment

Question 4

Pseudomonas tramission

Answer 4

contact person to person
fomites
aerosols

Question 5

Pseudomonas risk factors

Answer 5

Primary opportunist, nosocomial infection
disturbed barriers
immunocompromised
cystic fibrosis patients

Question 6

Pseudomonas virulent factors

Answer 6

Pili/flagellla
LPS (endotoxin)
Polysaccharide capsule
Exotoxin A (ETA)- inhibits protein synthesis by ADP-ribosylating EF2
Type III secreted toxins
degradative enzymes
** pathogenesis of pseudomonas is not well understood

Question 7

Disease caused by Pseudomonas

Answer 7

Pneumonia (HAP, VAP,)
bacteremia
endocarditis
skin/soft tissue
Osteomyelitis
UTI
Otitis Externa

Question 8

Pseudomonas Pneumonia:
common in what group?
presentation
diagnosis
prognosis

Answer 8

Pseudomonas pneumonia- major pathogen for HAP, VAP (rare in CA pneumonia, but seen in patients with chronic lung disease)
presentation- similar to CAP: fever, chill, purulent cough, dyspnea
Diagnosis- respiratory culture
prognosis- high mortality

Question 9

Pseudomonas Bacteremia

Answer 9

usually hospital acquired
high mortality
usually have primary infection site which lead to bacteremia
ecthymya gangrenosum - characteristic skin lesion

Question 10

Pseudomonas endocarditis

Answer 10

complication of bacteremia
rare but high mortality
mostly seen in IV drug users, patient with heavily damaged valves or persistent bacteremia

Question 11

Pseudomonas skin/soft tissue infections

Answer 11

Burn patients- pseudomonas is most common infection
wound infections- green/blue exudate, fruity odor
Whirlpool folliculitis- pruritic pustules, low grade fever
pseudomonas is everywhere, so when have a break in barrier, increased risk of infection

Question 12

Pseudomonas UTI

Answer 12

usually nosocomial related to catheterization

can proceed to bacteremia/sepsis

Question 13

Pseudomonas Otitis Externa

Answer 13

swimmer ear
infection of ear canal
painful when pull on pinna, push on tragus
Topical agent

Question 14

Treatment of Pseudomonas

Answer 14

Piperacillin-taxobactum
3rd/4th generation Cephalosporins (cefepime, ceftazidime)
aminoglycosides 
Carbapenems  (except Ertapenem)
Fluoroquinolones (Ciprofloxin)
Aztreonam
Polymyxins

** dont treat for pseudomonas unless you isolate it!