Introduction
Skin manifestations of hemochromatosis have been described by many authors, and studied comprehensively in a group of 100 patients by Chevrant-Breton et al.. These manifestations are usually overlooked by the patient, and sometimes by the physician. This chapter describes the clinical and histologic findings of skin abnormalities associated with hemochromatosis, complications of iron overload, and related disorders.
Skin pigmentation
Clinical aspects
Hyperpigmentation is one of the most characteristic signs of hemochromatosis, first named ‘bronzed diabetes.’ With diabetes mellitus and hepatic cirrhosis, this major symptom belonged to the classical triad of hemochromatosis. Today, this triad is exceptional and occurs in less than 10% of patients in recent studies. The frequency of pigmentation has changed progressively due to earlier diagnosis of hemochromatosis in many patients made possible by routine iron screening or family studies. The incidence of hyperpigmentation and other skin manifestations has therefore fallen from 98% (Fig. 27.1) to 72% in symptomatic cases5, to 5% in a series of Bacon et al.. Hyperpigmentation is absent in the children of homozygous subjects.
Hyperpigmentation is usually diffuse and generalized, but is prominent in sun-exposed areas. It involves the external genitalia of one-third of patients, and flexion folds, scars, buccal mucosae, and perilimbic conjunctivae in one-fifth of patients. The color of the pigmentation is often metallic gray (50% of cases), brown (20% of cases), or of mixed hue (30% of cases). It may be absent in persons with red hair. Progression of the increased pigmentation occurs very slowly, and is usually unnoticed by the patient or family members. Typically, it appears in the second decade.