Multiple Subcutaneous Nodules on the Torso and Leg

A healthy teenage girl presented with a history of a recurrent asymptomatic skin eruption. She had noted the gradual appearance of erythematous macules and reddish brown patches on her abdomen and lower extremities over a 1-month period. These areas would progressively fade to flesh tone or light brown during the winter and leave no scar. Similar macules and patches have recurred on an annual basis since the patient was 12 years old. She denied any history of preceding illness, prodromal symptoms, medication use, or easy bruisability. Her medical history and the results of the review of her symptoms were noncontributory.

On physical examination, the patient appeared well. There were several discrete erythematous macules and annular reddish brown patches extensively distributed over her abdomen and lower extremities (Figure 1). On closer examination, there was evidence of overlying telangiectasias, with slight central atrophy (Figure 2). The patches did not completely fade with pressure. The findings of the rest of the physical examination were unremarkable. Laboratory evaluation, including a CH₅₀ assay, antinuclear antibody titer, liver enzyme panel, prothrombin time, activated partial thromboplastin time, and complete blood cell count with differential cell count, revealed no abnormalities. To confirm the clinical impression, a skin biopsy specimen was obtained from a recent patch (Figure 3).

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