Pigmentary Changes of the Skin Associated With Internal Disease

Abstract

Pigmentary changes of the skin are present in almost all cases of phenylketonuria, alkaptonuria, pellagra and hemochromatosis. An appreciable percentage of patients with various other internal diseases may show cutaneous pigmentary changes that are diagnostically significant, e.g., freckles and seborrheic keratoses, unilateral epidermal nevi, incontinentia pigmenti, lentiginosis centrofacialis, and poikiloderma. The different types of acanthosis nigricans are discussed.