Generalized epidermolytic hyperkeratosis in the child of a parent with nevus comedonicus.

Nevus comedonicus (NC) is rarely associated with the histopathologic changes of epidermolytic hyperkeratosis (EH). A parent with mild focal NC had a child with severe generalized EH. The histopathologic findings of skin biopsy specimens from parent and child showed the distinctive granular and spinous layer vacuoles and coarse keratohyaline granules of EH. This parent and child may be examples of the extremes in expression of an autosomal dominant trait.