Community-Acquired Pneumonia Flashcards
7 cards from real Internal Medicine Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Community-Acquired Pneumonia flashcards as text
A 55-year-old with alcoholism presents with right upper lobe pneumonia and foul-smelling sputum. What organism is the most likely cause?
Answer: Anaerobes / aspiration flora
Aspiration pneumonia in alcoholics involves anaerobic organisms from the oropharynx and classically affects dependent lung segments with putrid sputum.
Which radiographic pattern is MOST characteristic of Pneumocystis jirovecii pneumonia (PCP) in an immunocompromised host?
Answer: Bilateral interstitial/perihilar infiltrates
PCP classically presents with bilateral perihilar interstitial infiltrates on CXR, often with a ground-glass pattern on CT.
A 70-year-old develops CAP. Blood cultures are ordered. According to IDSA guidelines, blood cultures are routinely recommended in which scenario?
Answer: CAP requiring ICU admission
Current IDSA guidelines recommend blood cultures primarily for severe CAP requiring ICU care, not for all hospitalized patients.
Legionella urinary antigen testing detects which serogroup of Legionella pneumophila?
Answer: Serogroup 1 only
The Legionella urinary antigen test detects only serogroup 1, which causes approximately 70–80% of Legionella pneumonia cases.
Which clinical feature is MOST helpful in distinguishing Legionella pneumonia from pneumococcal pneumonia?
Answer: Hyponatremia + GI symptoms + elevated LFTs
Legionella characteristically causes hyponatremia, diarrhea, abdominal pain, and transaminase elevation in addition to pneumonia.
What is the appropriate duration of antibiotic therapy for uncomplicated, mild-to-moderate CAP that shows clinical improvement?
Answer: 5 days
Current evidence supports 5-day courses for uncomplicated CAP in patients who show clinical stability by day 3.
A 65-year-old with CAP and no comorbidities is treated as an outpatient. Which antibiotic is appropriate as monotherapy?
Answer: Azithromycin (if low macrolide resistance)
Azithromycin monotherapy is appropriate for outpatient CAP in healthy patients without comorbidities in areas with low macrolide resistance (<25%).