Melanin Pigmentation

Abstract

Clinical Disorders of Melanin PigmentationAlthough considerable knowledge of the biology of mammalian melanin formation is now available, the pathogenesis of only a very few of the large number of pigmentary disorders is known. Four prototypes have been selected for discussion. The conditions to be discussed (albinism, phenylketonuria, ephelides and Addison's disease) are neither the most common nor the most important, but the mechanism of the pigmentary change in each is reasonably well understood.ClassificationPigmentary disorders involving the melanocyte system can be divided on a morphologic basis into three major categories: decreased pigmentation (white or lighter than patient's normal . . .