Dowling-Degos disease (DDD) is an autosomal dominant genodermatosis characterized by reticular pigmentation, usually in a flexural distribution. However, generalized DDD can also occur, with numerous hypopigmented or erythematous macules and papules on the neck, chest, and abdomen. The histopathology of DDD shows characteristic thin branch-like patterns of epidermal downgrowth (summary by Li et al., 2013).
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, reticulate acropigmentation of Kitamura (RAK), reticulate acropigmentation of Dohi (DSH, RAD; 127400), 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.
For a discussion of genetic heterogeneity of reticulate pigment disorders, see 179850. [from
OMIM]