Community-Acquired Pneumonia

Question 1

Definition of CAP

Answer 1

inflammation of lung parenchyma acquired outside hospital/health-care setting producing alveolar exudate and consolidation.

Question 2

Most common bacterial cause of CAP

Answer 2

strep. pneumoniae most common

Question 3

bacterial causes of CAP

Answer 3

moraxella catarrhalis
staph aureus
h influenza
MRSA
group A strep
legionella pneumophila
mycoplasma pneumophila
chlamydia pneumoniae

Question 4

viral causes of CAP

Answer 4

RSV
parainfluenza (children)
influenza A and B (adults)
adenovirus (military)

Question 5

pathophysiology of CAP

Answer 5

pathogens can reach via inhalation, oropharyngeal aspiration, haematogenous spread, or direct infection from adjacent foci (TB).
- invasion and overgrowth in lung parenchyma -> intra-alveolar exudate (consolidation)
- impaired immune response (HIV-AIDs, advanced age) or defence dysfunction (smoking, COPD) greater susceptibility

Question 6

Risk of factors of CAP

Answer 6

> 65 years
resident in healthcare setting
COPD
exposure to cigarette smoke
alcohol abuse
poor oral hygiene
contact with children
acid-reducing drugs
diabetes mellitus
chronic renal disease
chronic liver disease
opioids