Antimicrobials USMLE Step 1 Practice Question
A 30-year-old pregnant woman with HIV infection started on zidovudine (AZT) for vertical transmission prophylaxis presents with progressive fatigue and dyspnea on exertion. Vital signs show HR 102/min, RR 18/min, BP 118/76 mmHg, and Temp 37°C. Laboratory studies reveal macrocytic anemia with hemoglobin 7.2 g/dL and elevated MCV of 108 fL. Reticulocyte count is inappropriately low. Peripheral blood smear shows no schistocytes. Which nucleoside reverse transcriptase inhibitor is most likely responsible?
Answer choices
- AEfavirenz
- BZidovudineCorrect answer
- CMaraviroc
- DRitonavir
- EAcyclovir
- FLamivudine
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