Pneumonia USMLE Step 1 Practice Question
A 68-year-old man admitted with acute stroke develops dysphagia. Two days later, he presents with fever (38.9°C), productive cough with foul-smelling purulent sputum, and tachypnea (RR 22). Vital signs show BP 142/88, HR 98, SpO2 94% on room air. Chest radiograph demonstrates right lower lobe infiltrate with air-bronchograms. Sputum culture grows anaerobic bacteria. He denies recent antibiotic use. Which of the following is the most likely underlying cause of this pneumonia?
Answer choices
- AAspiration pneumonia due to anaerobesCorrect answer
- BPulmonary embolism
- CLegionella pneumophila
- DStreptococcus pneumoniae
- EMycoplasma pneumoniae
- FPneumocystis jirovecii pneumonia
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