Dysfunction of melanocytes in photoleukomelanoderma following photosensitivity caused by hydrochlorothiazide.

We report a 68-year-old Japanese man who developed photoleukomelanoderma following prolonged photosensitivity caused by hydrochlorothiazide. He showed complete recovery from the leukomelanoderma with the discontinuation of the responsive drug and with topical application of tacrolimus hydrate and corticosteroid. Histological and immunohistochemical examination revealed that there were no melanin-positive cells in the hypopigmented area, despite the presence of melanocytes.