Acral keratoderma.

Three siblings displayed an unusual form of keratoderma characterized by diffuse and striate hyperkeratosis of the palms and soles, hyperkeratotic plaques over the dorsum of the hands and toes, and linear hyperkeratotic lesions over the Achilles tendon area, ankles, elbows, and knees. The predominant location of these lesions led to the term acral keratoderma for this disorder. Histologically, besides thickening of all epidermal layers with that of the stratum corneum being most notable, various dyskeratotic changes were evident in the epidermis. Pedigree analysis of the family suggested an autosomal recessive inheritance pattern. There were similarities and differences between the type of keratoderma displayed by these three patients and that of patients described previously with the disorder known as keratoma hereditarium mutilans.