Incidental epidermolytic hyperkeratosis.

Epidermolytic hyperkeratosis is the distinctive histopathologic change that has been described as the main feature of bullous congenital ichthyosiform erythroderma and as an incidental finding in other cutaneous disorders. We retrospectively evaluated our cases of incidental epidermolytic hyperkeratosis over a 5-year period, and reviewed the conditions that have been associated with incidental epidermolytic hyperkeratosis. We identified 21 individuals (14 men and seven women), ranging in age from 3 to 87 years, in whom incidental epidermolytic hyperkeratosis was found. Lesions in which the pathologic changes of incidental epidermolytic hyperkeratosis have been reported include dermal fibrohistiocytic lesions, epithelial neoplasms, hereditary disorders, inflammatory conditions, and melanocytic neoplasms. The histogenesis of incidental epidermolytic hyperkeratosis remains to be determined.