A 17-year-old female developed diffuse blue-gray pigmentation of both shins over a two-month period, the right leg more involved than the left. At first she thought the discoloration represented abnormal bruising from her soccer practices; however, the area continued to darken and expand. The patient was otherwise healthy. Her only medication was minocycline, which she had been taking for 18 months to treat acne with no side effects. Laboratory tests were normal.

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