Pseudomonas aeruginosa Flashcards Preview

Microbiology Block 3 > Pseudomonas aeruginosa > Flashcards

Flashcards in Pseudomonas aeruginosa Deck (19):
1

what is the biology of pseudomonas aeruginosa?

Gram negative rod, Oxidase + *, NLF on MA

Aerobic *(non-fermentative)

Alginate capsule * 

Produces pigments * (Pyocyanin – blue-green *)

 

2

what odor does P. aeruginosa have?

Grape-like / fruity aroma*

 

3

where can we find pseudomonas aeruginosa growing?

  • In hot tubs, sinks, vases *
  • In hospitals – contaminates intravenous tubing, respiratory therapy equipment *

4

where is P.aeruginosa a Significant Opportunistic pathogen * *?

 

  • Compromised lung function
  • Cystic fibrosis patients
  • Immunocompromised Diabetic patients

5

what is P. aeruginosa a major cause of?

 Major cause of Nosocomial infections * *

 

6

What strains cause  significant respiratory tract infections in Cystic fibrosis patients *

 

 Mucoid strains cause significant respiratory tract infections in Cystic fibrosis patients *

7

what 3 toxins can we find in P. aeruginosa?

Exotoxin A

Pyocyanin

Phospholipase C

Endotoxin (LPS)

8

what does Exotoxin A do?

blocks protein synthesis at EF-2

9

what will Pyocyanin do?

tissue damage (catalyzes production of H2O2 and superoxide)

10

what will phospholipase C toxin do?

tissue damage (Breaks down lipids and lecithin)

11

P. aeruginosa infection will lead to what diseases?

  • Swimmer’s ear * (Otitis externa)
  • Hot tub folliculitis*
  • Infect burn wounds/surgical wounds *

  • Eye infections
  • “Malignant” /necrotizing otitis externa *
  • Osteochondritis (infection of bone and cartilage) *
  • Pulmonary infections *

  • UTI *

12

Septicemia with pseudomonas aeruginosa will be caused by what infections?

 what can it lead to?

asscociated with pulmonary infections, UTI, skin/soft tissue infections

 

Ecthyma gangrenosum * (hemorrhagic pustule with surrounding erythema -> necrotic ulcer (black center))

 

13

in what pts will p. aeruginosa lead to pneumonia?

  • Cystic fibrosis patients* (recurrent pneumonias → highly mucoid strains)
  • Neutropenic patients * (Pneumonia & Septicemia)
  • Chronic granulomatous disease (CDG) patients * (Pneumonia + septicemia)

14

wounds infected with p. aeruginosa will have what color?

Green discoloration of a postoperative wound

15

what tests can be used on p. aeruginosa in order to identify it?

  • positive oxidase test *
  • blue-green pigmentation *
  • Fruity smell *

16

what drug resistance mechanisms does p. aeruginosa use in order to become resistant?

  • Altered Porin proteins *– major mechanism – allows bacterial cell to develop resistance to multiple antibiotics simultaneously
  • Beta-lactamases *
  • Multi-drug Efflux pumps *

17

what treatment is used to treat drug resistant p.aeruginosa?

  • Antipseudomonal beta-lactam  + aminoglycoside

Piperacillin + Tobramycin

  • Antipseudomonal penicillin + beta-lactamase inhibitor

Piperacillin + Tazobactam

 

18

what are the anti-pseudomonal penicillins?

 

 

Carbenicillin

Piperacillin

Ticarcillin

19

what are the Anti-pseudomonal cephalosporins?

 

Ceftazidime