Mycology/Parasitology USMLE Step 1 Practice Question
A 68-year-old man with COPD and prior pulmonary tuberculosis presents with hemoptysis and dyspnea. Vitals: BP 138/82, HR 92, RR 22, Temp 37.2°C, SpO2 88% on room air. High-resolution CT chest shows a 3-cm cavitary lesion with an intracavitary mobile mass. Sputum culture grows septate hyphae with acute-angle branching. Chest X-ray shows no pneumothorax. He denies fever or weight loss. Which organism is most likely responsible?
Answer choices
- AMucormycosis
- BCoccidioidomycosis
- CHistoplasmosis
- DAcute invasive aspergillosis
- EAspergillomaCorrect answer
- FCryptococcus neoformans
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.