Pneumonia USMLE Step 1 Practice Question
A 34-year-old man with untreated HIV presents with 3 weeks of progressive dyspnea, nonproductive cough, and chest tightness. He reports fever to 38.5°C. Vital signs show HR 102/min, RR 28/min, BP 118/76 mmHg, and SpO2 88% on room air. CD4 count is 45 cells/μL. Chest X-ray demonstrates bilateral interstitial infiltrates with ground-glass opacification. Sputum culture remains negative. He denies hemoptysis. Which of the following is the most likely diagnosis?
Answer choices
- APneumocystis jirovecii pneumoniaCorrect answer
- BCytomegalovirus pneumonitis
- CAspergillus fumigatus infection
- DStreptococcus pneumoniae pneumonia
- EMycobacterium tuberculosis infection
- FHistoplasma capsulatum infection
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