Pseudomonas Aeruginosa

Question 1

P. aeruginosa general info

Answer 1

Associated with:
Burns
Catheters
Implanted medical devices
Ventilator associated pneumonia
Eye wounds
can cause bacteremia in immunocompromised patients
chronic infections generally occur in the lung in association with respiratory diseases such as CF or COPD
-people with genetic CF are susceptible to chronic bacterial infection that cannot be cleared by any current antimicrobial therapies–pts usually die of respiratory failure in early adulthood
-in CF lung, clearance is impeded by host factors and bacterial factors

Question 2

P. aeruginosa toxins

Answer 2

secretes a number of toxins that contribute to its pathogenicity
endotoxin- just like other gram-negative organisms
exotoxins- proteases (elastases) and phospholipases
-elastases break down elastin, a connective tissue in the lung and can lead to tissue damage in the lung
Phospholipase- break down phospholipids in lung surfactant and in host cell membranes
-some toxins secreted by T3SS

Question 3

P. aeruginosa lab ID

Answer 3

produces a blue-pigment called pyocyanin (which is also a virulence factor that generates ROS)
since it cannot ferment sugars, detection in blood culture requires aerobic incubation.
While P. aeruginosa can grow via anaerobic respiration with nitrate as an electron acceptor, or ferment amino acid arginine, it is considered an obligate aerobe