Antimicrobials USMLE Step 1 Practice Question
A 34-year-old man with advanced HIV (CD4 count 45 cells/μL) presents with progressive dyspnea, fever 38.5°C, and hypoxemia (SpO2 88% on room air). Chest X-ray shows diffuse bilateral ground-glass opacities. Bronchoalvestalveolar lavage confirms Pneumocystis jirovecii infection. He denies sulfa allergy. He is prescribed a drug combination that sequentially blocks folate synthesis at different enzymatic steps. Which antimicrobial pair was most likely prescribed?
Answer choices
- ATrimethoprim and sulfamethoxazoleCorrect answer
- BVancomycin and gentamicin
- CAmoxicillin and clavulanate
- DAcyclovir and ganciclovir
- EIsoniazid and rifampin
- FPentamidine and atovaquone
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