A case of Dohi presenting with diffuse pigmented patch on both dorsum of hands

Abstract

Reticulated acropigmentation of Dohi (RAD), dyschromatosis symmetrica hereditaria, is the localized acral form of dyschromatosis universalis hereditaria that has an autosomal dominant pattern of inheritance. RAD is characterized by the mixed hyperpigmented and hypopigmented macules and its bilaterally symmetrical distribution on the back of the hands and feet, wrists, knees, and elbows. The presented case is a 18-year-old female had relatively well demarcated symmetric hyperpigmented and hypopigmented macules and patches on dorsa of hands and feet, forearms, lower legs and face. These pigmentations at first appeared at 3 years old on dorsa of her fingers and toes, thereafter these pigmentations spread progressively to the proximal portion of her body. Her pedigree shows autosomal dominant pattern of inheritance. Histologically, there is markedly decreased basal pigmentation with preserved melanocytes. Immunohistochemical stain for the Melan-A revealed both areas of either decreased or increased Melan-A positive melanocytes in basal layer, which suggests that Reticulated acropigmentation of Dohi is a genetic disorder of functional derangement of melanocytes.