A 15-year-old girl presented with a rash on both feet that had appeared a month earlier. Initially the rash looked like bruising at the base of both large toenails (Figure 1); it then spread as purple macules and papules to the plantar and dorsal surfaces of several toes. The lesions were slightly itchy at times, but not painful, and had steadily increased in number over the past few weeks.
The patient plays competitive soccer and had played 4 games in the cold rain before the rash appeared but said her feet hadn’t been injured. There were no other lesions on her legs or torso. The rash hadn’t developed in her family members and the family had not traveled recently.
The patient’s medical history included exercise-induced asthma and chronic headaches. She was using inhaled beclamethasone and albuterol for asthma and amitryptyline 30 mg daily to prevent headaches She appeared well, had no fever, and her vital signs were normal.
The patient’s toes appeared dusky in color and were cold to the touch. The purple skin at the base of the big toenails was not tender and there were no ulcerations or blisters. There were multiple erythematous, violaceous papules on both feet, primarily on the toes (Figures 2 and 3). The rest of her skin was clear. The patient refused a skin biopsy because it would interfere with her active soccer schedule.
Laboratory values were normal for ANA, CBC, cryoglobulins, and CH50. A cold agglutinins titer was elevated (1:80; normal, none detectable).
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