Aplasia cutis congenita with hair collar sign and dermal melanocytosis

摘要

Editor,Aplasia cutis congenita is a rare congenital malformation of the skin characterized by the localized absence of skin that involves the epidermis, dermis, and subcutaneous fat. The "hair collar sign", a designation introduced by Commens et al. in 1989, is characterized by the presence of a ring of terminal hairs around any cutaneous lesion. It has been described as a relatively specific marker of neuroectodermal defects. We report a rare case of aplasia cutis congenita associated with a hair collar and dense dermal melanocytosis.