Kerinokeratosis papulosa with a type 2 segmental manifestation

Kerinokeratosis papulosa is a synonym for "waxy keratoses of childhood" (Greek kerinos = waxy). Affected children show multiple disseminated shiny papules involving the entire skin, with a preponderance on the trunk, the upper arms, and the thighs. We describe an additional case supporting the notion that this is a distinctive disorder of keratinization. In this case, the disorder was superimposed by a linear area of excessive involvement affecting the left arm in the form of an epidermal nevus with a shiny, waxy appearance. This linear lesion may be best explained as a type 2 segmental manifestation of the disorder, which would imply that kerinokeratosis papulosa is inherited as an autosomal-dominant trait.