Pneumonia USMLE Step 1 Practice Question
A 55-year-old man with poorly controlled diabetes and chronic alcoholism presents with fever (39.2°C), productive cough with foul-smelling purulent sputum, and dyspnea. Vital signs show BP 128/76 mmHg, HR 102/min, RR 22/min, SpO2 92% on room air. Chest X-ray demonstrates a right lower lobe infiltrate with an air-fluid level. Laboratory studies reveal WBC 14,200/μL. He denies recent aspiration events. Which organism is most likely responsible?
Answer choices
- AStreptococcus pneumoniae
- BPeptostreptococcus and Prevotella speciesCorrect answer
- CMycobacterium tuberculosis
- DHaemophilus influenzae
- ELegionella pneumophila
- FPseudomonas aeruginosa
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