Antimicrobials USMLE Step 1 Practice Question
A 25-year-old man presents to his primary care physician with a 3-day history of painful grouped vesicles on the shaft of the penis associated with mild fever, malaise, and tender inguinal lymphadenopathy. He reports a new sexual partner two weeks prior and denies any similar episodes in the past. His temperature is 38.1°C, heart rate is 88/min, blood pressure is 122/76 mmHg, and respiratory rate is 16/min. Physical examination reveals multiple 2–3 mm fluid-filled vesicles on an erythematous base along the penile shaft, with no urethral discharge. PCR of the vesicular fluid confirms herpes simplex virus type 2 infection. He is started on a guanosine analog that must first be phosphorylated by viral thymidine kinase and subsequently inhibits viral DNA polymerase by acting as a chain terminator. Which of the following drugs was most likely prescribed?
Answer choices
- AZidovudine
- BRibavirin
- CAcyclovirCorrect answer
- DFoscarnet
- EOseltamivir
- FGanciclovir
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