Mycology/Parasitology USMLE Step 1 Practice Question
A 28-year-old man recently returned from caving in Arizona presents with a 2-week history of productive cough and fever (38.5°C). Vital signs show HR 102 bpm, RR 20/min, BP 118/76 mmHg, and SpO2 98% on room air. Chest X-ray demonstrates hilar lymphadenopathy without cavitary lesions. Sputum culture grows a dimorphic fungus appearing as small spheres containing endospores at 37°C. He denies hemoptysis. Which of the following is the most likely diagnosis?
Answer choices
- AHistoplasmosis
- BCoccidioidomycosisCorrect answer
- CTuberculosis
- DAspergillosis
- EBlastomycosis
- FCryptococcosis
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