CASE
A 4-month-old white female presented with a solitary "bump" on her back. Thinking the bump was a bug bite, the mother had applied hydrocortisone cream, with no effect. At times the lesion appeared flat and nonpalpable, but at other times, it was raised and "puffy." The infant was in otherwise good health. Her medical history was significant for intrauterine growth restriction; she was delivered without complication at 37 weeks' gestation. A review of systems revealed no abnormalities.
The infant appeared alert and well-nourished. A solitary 6×4-mm pink nodule was noted on the left posterior aspect of the torso (Figure 1). No scale or vesicles were seen. Rubbing the lesion caused it to urticate.
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