Viral Infections USMLE Step 1 Practice Question
A 3-year-old boy presents with high fever (104.2°F) for 4 days followed by abrupt defervescence and appearance of a generalized maculopapular rash on the trunk sparing the face. Vital signs: HR 110/min, RR 24/min, BP 105/68 mmHg, SpO2 98% on room air. The rash is nonpruritic and does not blanch. Laboratory studies show leukocytosis (12,500/μL) with relative lymphocytosis. He denies oral ulcers or conjunctival injection. Which of the following is the most likely diagnosis?
Answer choices
- AMeasles
- BRoseola infantumCorrect answer
- CScarlet fever
- DErythema infectiosum
- ERubella
- FKawasaki disease
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