Familial eruptive vellus hair cysts.

Eruptive vellus hairs cysts are benign papules consisting of small cysts containing multiple vellus hairs. An eruption commonly develops on the chest and sometimes the upper extremities. These papules are asymptomatic or rarely pruritic. Only a few cases of familial association have been described. We report the development of eruptive vellus hair cysts on the trunk of an 8- and 12-year-old sister and brother.