A 23-month-old girl with a history of mild atopic dermatitis presented for evaluation of a rash. The rash first appeared 3 days previously on her arms and legs and progressed rapidly to also involve her face and torso. A transient fever was reported when the rash first appeared. There was no history of cough, rhinorrhea, nausea, vomiting, abdominal pain, diarrhea, or arthralgias. She was not receiving any medications. She attended day care, where at least 1 other child reportedly had been ill with fever and rash.
Cutaneous examination was notable for a well-appearing toddler in no acute distress. Numerous discrete and coalescing 2- to 10-mm erythematous papules and hemorrhagic vesicles, many of which were crusted, were noted on both arms, both hands, both legs, and the dorsal aspect of her feet, with lesser involvement of the torso, buttocks, and perioral region (Figure 1 and Figure 2). A few scattered small erosions were noted on the oral mucosa. The remainder of the examination findings were unremarkable except for a few scattered eczematous patches on the extremities. A diagnostic test was performed to confirm the diagnosis.
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