Mycology/Parasitology USMLE Step 1 Practice Question
A 32-year-old woman with newly diagnosed HIV presents with dyspnea, fever (38.5°C), and nonproductive cough for 2 weeks. Vital signs show BP 110/68, HR 102, RR 24, SpO2 88% on room air. CD4 count is 85 cells/μL. Chest X-ray demonstrates bilateral interstitial infiltrates. Sputum induction reveals foamy, pale-staining organisms on Giemsa stain. She denies chest pain. She is not currently on antiretroviral therapy. Which organism is most likely responsible?
Answer choices
- AAspergillus fumigatus
- BCoccidioides immitis
- CPneumocystis jiroveciiCorrect answer
- DHistoplasma capsulatum
- ECryptococcus neoformans
- FCytomegalovirus pneumonitis
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