This 16-year-old boy had slowly progressive hypopigmented lesions on the lower extremities for the past 4 years. He also had atopic dermatitis, asthma, and allergic rhinitis. His 38-year-old mother had Hashimoto thyroiditis. None of his immediate family members had a similar skin disorder.
Well-demarcated, depigmented patches on extensor aspects of lower legs. Remaining findings unremarkable.
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