A 21-year-old woman presented with a rash on her right thigh of 3 to 4 months’ duration. She reported that the patch was asymptomatic. She was not taking any medications and otherwise was in good health. A review of systems was negative. The patient was a student who used her laptop frequently. On physical examination, a 10×5-cm reticulated, hyperpigmented patch was seen on her right thigh (FIGURE).
