Viral Infections USMLE Step 1 Practice Question
A 2-year-old unvaccinated boy presents with a 3-day history of high fever (39.8°C), cough, bilateral conjunctivitis, and coryza. He now develops an erythematous maculopapular rash on his face spreading downward to his trunk and extremities. Physical examination reveals pathognomonic white spots on the buccal mucosa opposite the molars. Serum IgM is positive. He denies recent antibiotic use. Which of the following is the most likely diagnosis?
Answer choices
- ARoseola infantum
- BVaricella
- CRubella
- DScarlet fever
- EMeaslesCorrect answer
- FFifth disease (erythema infectiosum)
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