E1- Bacterial Pneumonia II Flashcards
What are the most common pathogens of HAP?
Pseudomonas aeruginosa*
Stapholococcus aureus
Klebsiella pneumoniae
Is Pseudomonas aeruginosa gram positive or gram negative? What shape?
Gram negative bacillus
What type of environments does Pseudomonas aeruginosa like?
Wet envrionements (cut flowers, food, sinks, toilets, dialysis equipment, disinfectants)
What color is Pseudomonas aeruginosa?
Blue-green
Pyoverdin, pyocyanin
What is unique about Pseudomonas aeruginosa?
Non-fermenting
What can Pseudomonas aeruginosa use as a terminal electron acceptor?
Nitrate
What kind of pathogen is Pseudomonas aeruginosa?
Opportunistic, rarely infects healthy individuals
What are the five virulence factors of Pseudomonas aeruginosa?
Adhesins Alginate capsule Pyocyanin Exotoxin A Elastases
What virulence factors of Pseudomonas aeruginosa is important for cyclic fibrosis patients?
Alginate capsule
Inhibits mucocilary escalator
How does pyocyanin act as a virulence factor in Pseudomonas aeruginosa?
Catalyze ROS and causes tissue damage
What elastases does Pseudomonas aeruginosa have? How do they work?
LasA and LasB
Work synergistically to degrade elastin (30% of the lung tissue is elastin)
What diseases can Pseudomonas aeruginosa cause?
Pneumonia (HAP)*
Urinary tract
Eye, ear, skin
Second leading cause of infection in burn pts
Common cause of death in cystic fibrosis pts
Sepsis
What population commonly gets chronic and recurrent Pseudomonas aeruginosa infections in the respiratory tract?
Cystic fibrosis pts
How is Pseudomonas aeruginosa pneumonia (HAP) dx?
Gram stain
Culture
Why is treatment of Pseudomonas aeruginosa pneumoniae (HAP) difficult?
Notoriously resistant to abx (capsule)
Pts are typically immunocompromised
Acquisition of resistance mediators
Can you prevent a Pseudomonas aeruginosa infection?
No, you can only hope to contain it
Prevent contamination of sterile equipment
Prevent pt to pt spread
What are the common pathogens that cause atypical pneumoniae?
Legionella pneumoniae
Mycoplasma pneumoniae
Chlamydophila pneumoniae
What disease can mycoplasma pneumoniae cause?
Atypical CAP