Elastosis perforans serpiginosa.

A 41-year-old white man with Down syndrome presented with a slightly pruritic, papular eruption on bilateral forearms of several years' duration. Physical examination revealed multiple 2- to 3-mm keratotic, umbilicated pink papules in an annular configuration distributed symmetrically on the flexural surfaces of the forearms (Figure 1). The skin surrounding these papules was noted to be hyperpigmented and somewhat atrophic.