Nail changes of punctate keratoderma: a clinical and pathological study of two patients.

The pathological study of the nail changes of 2 patients affected by punctate keratoderma is described. Both patients presented nail abnormalities that were clinically suggestive of a nail psoriasis. Subungual hyperkeratosis was a prominent feature but onycholysis, splinter haemorrhages and pitting were also present. The pathology of the nail bed revealed sharply limited columns of hyperkeratosis associated with hypergranulosis and depression of the underlying nail bed epidermis. Etretinate therapy produced a significant improvement in the palmoplantar keratoderma, but it was of no apparent value in treating nail keratoderma.