Viral Infections USMLE Step 1 Practice Question
A 24-year-old previously healthy woman presents with fever (39.2°C), sore throat, and diffuse lymphadenopathy. She reports taking amoxicillin for pharyngitis 3 days ago. On examination, she has splenomegaly and a prominent maculopapular rash on her trunk and extremities. Vital signs: HR 102/min, RR 18/min, BP 118/76 mmHg, SpO2 98% on room air. Monospot test is positive; atypical lymphocytes noted on peripheral blood smear. No petechiae are present. Which of the following best explains the rash?
Answer choices
- ASecondary syphilis occurring coincidentally
- BStreptococcal scarlet fever superimposed on mononucleosis
- CAmoxicillin-induced drug reaction in the setting of EBV infectionCorrect answer
- DErythema multiforme from EBV reactivation
- EMeasles infection concurrent with EBV
- FAcute HIV infection with opportunistic fungal rash
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