Dyschromatosis universalis hereditaria: two cases in a Chinese family.

Two cases of dyschromatosis universalis hereditaria (DUH) from a Chinese family are presented. Case 1 was a 62-year-old woman who had a generalized and progressive hyper- and hypopigmentation of the skin from the age of 8 years. Her brother had also developed a similar skin pigmentary defect from about the same age. Histopathological and ultrastructural examination of lesional skin showed increased melanin content in epidermal keratinocytes but no changes in the appearance or number of melanocytes. Although hereditary defects may influence melanogenesis resulting in a pigmentary anomaly, the pathogenesis of DUH remains unclear.