Viral Infections USMLE Step 1 Practice Question
An 11-year-old girl is brought to the clinic by her mother with a 3-day history of an erythematous rash on her trunk and extremities. The mother reports that 1 week ago, the patient developed low-grade fever (38.1°C), rhinorrhea, and mild headache that resolved over 2 days. Two days ago, a bright red facial rash appeared that spared the perioral region. On examination, vital signs are normal except for a temperature of 37.8°C (100°F). The facial rash is well-demarcated and blanching. On her forearms and thighs, the examiner notes a lace-like reticular pattern of erythema with central clearing. She reports mild pruritus but denies oral lesions, arthralgia, or conjunctivitis. Which of the following is the most likely diagnosis?
Answer choices
- ARubella
- BMeasles
- CErythema infectiosumCorrect answer
- DScarlet fever
- EDrug reaction (ampicillin)
- FRoseola infantum
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