ABSTRACT
Reticular hyperpigmentation is a clinical feature that has been associated with a wide spectrum of disorders, including both congenital and acquired diseases. This type of hyperpigmentation is encountered in disorders such as Dowling–Degos disease (DDD), acropigmentation of Kitamura, and incontinentia pigmenti (IP). This chapter summarizes of all diseases that can present with reticular hyperpigmentation. Histopathological examination may also assist in setting the correct diagnosis. Disorders such as acropigmentation of Kitamura, DDD, Galli–Galli disease (GGD), and confluent and reticulate papillomatosis of Gougerot and Carteaud (CARP) typically present with epidermal changes seen in the histopathological examination. X-linked reticulate pigmentary disorder (XLPDR) is a very rare genodermatosis that is inherited as an X-linked trait. There are no specific treatment options for the disorder, and therefore, supportive care is recommended. Genetic counseling for families with one child affected by XLPDR and planning future pregnancies should be strongly encouraged.
