Dowling-degos disease (DDD) is a rare genodermatose inherited as autosomal dominant trait characterized by brown to black macules located symmetrically in flexural sites. Lesions are not congenital, and the age of onset is highly variable. It is more common in women. Herein, we present the case of a male patient whose clinical and histopathological findings are consistent with DDD and then review existing literature. A 35-year-old male patient presented to the dermatology clinic with black lesions in his flexural sites since childhood. He had no subjective symptoms such as itching or pain in his symmetrically located lesions. His mother and cousins had similar lesions. On the histopathological examination of the lesion sample taken from the inguinal region, fine filiform branchings were found in the epidermis, the rete ridges showed tendency to merge, and there was budding in the rete ridges, which showed hyperpigmentation. The adjacent epidermis showed keratin cysts and mild perivascular mononuclear inflammatory cell infiltration in the superficial dermis. Based on these histopathological findings, the diagnosis was DDD. Fractional erbium YAG laser yielded good clinical outcome.
DDD should be kept in mind in the differential diagnosis of hyperpigmented lesions in flexural sites.