Pneumonia USMLE Step 1 Practice Question
A 55-year-old man with a 2-month history of productive cough, night sweats, and 8-pound weight loss presents with hemoptysis. Vital signs show temperature 38.5°C, heart rate 92/min, respiratory rate 18/min, blood pressure 128/82 mmHg, and SpO2 98% on room air. Chest radiograph reveals cavitary lesions in bilateral lung apices. Sputum Gram stain shows acid-fast bacilli. He denies recent sick contacts. Which organism is most likely responsible for this infection?
Answer choices
- ATuberculosisCorrect answer
- BPulmonary embolism
- CStaphylococcus aureus pneumonia
- DKlebsiella pneumoniae
- EHistoplasma capsulatum
- FMycobacterium avium complex
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