Symmetrical dyschromatosis of extremities

Dyschromatosis symmetrica hereditaria (DSH), also called symmetric dyschromatosis of the extremities and symmetric or reticulate acropigmentation of Dohi (Komaya, 1924), is characterized by hyperpigmented and hypopigmented macules on the face and dorsal aspects of the extremities that appear in infancy or early childhood. DSH generally shows an autosomal dominant pattern of inheritance with high penetrance. The condition has been reported predominantly in Japanese and Chinese individuals. Review of Reticulate Pigment Disorders Muller et al. (2012) reviewed the spectrum of reticulate pigment disorders of the skin, tabulating all reported cases of patients with Dowling-Degos disease (see DDD1; 179850), reticulate acropigmentation of Kitamura (RAK; 615537), reticulate acropigmentation of Dohi (RAD), Galli-Galli disease (GGD), and Haber syndrome (HS). Of 82 cases, 26 (31.7%) were clinically diagnosed as DDD, 13 (15.9%) as RAD, 11 (13.4%) as GGD, 8 (9.8%) as RAK, and 8 (9.8%) as HS; in addition, 16 (19.5%) of the cases showed overlap between DDD and RAK. Muller et al. (2012) also published photographs of an affected individual exhibiting an overlap of clinical features of DDD, GGD, RAD, and RAK. The authors noted that in reticulate disorders of the skin, the main disease entity is DDD, with a subset of cases exhibiting acantholysis (GGD), facial erythema (HS), or an acral distribution (RAD; RAK). Muller et al. (2012) concluded that all reticulate pigment diseases of the skin are varying manifestations of a single entity. Genetic Heterogeneity of Reticulate Pigment Disorders For a discussion of genetic heterogeneity of reticulate pigment disorders, see 179850. [from OMIM]