Mycology/Parasitology USMLE Step 1 Practice Question
A 34-year-old woman with HIV/AIDS (CD4 count 85 cells/μL) presents with progressive dyspnea, fever, and dry cough for 3 weeks. Vital signs show temperature 38.5°C, heart rate 108/min, respiratory rate 28/min, and oxygen saturation 88% on room air. Chest X-ray demonstrates bilateral interstitial infiltrates. Sputum staining with silver stain reveals cup-shaped organisms. She denies chest pain. Which of the following is the most likely diagnosis?
Answer choices
- AHistoplasmosis
- BCytomegalovirus pneumonia
- CPneumocystis jirovecii pneumoniaCorrect answer
- DTuberculosis
- EAspergillosis
- FCryptosporidium parvum infection
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