Dowling–Degos disease with reticulate acropigmentation of Kitamura: Extended spectrum of a single entity

Dowling–Degos disease (DDD) and reticulate acropigmentation of Kitamura (RAK) are rare genodermatoses inherited as an autosomal dominant trait with variable penetrance. They are considered to be part of a spectrum of reticulate pigmentary dermatoses, characterized by the presence of hyperpigmented macules coalescing in a reticular fashion. The authors describe a 28-year-old male patient having hyperpigmented macules on the axillae, neck and face, reticulate acropigmentation of dorsum of the hands, forearms and feet, palmar pitting, and comedo-like lesions over back. The patient showed the unique clinical as well as histopathological overlap of both the rare diseases (DDD and RAK), substantiating the hypothesis that they represent two different features of a single entity with variable phenotypic expression.