Nevus depigmentosus: review of a mark of distinction.

Nevus depigmentosus (ND), also known as nevus achromicus or achromic nevus, is an uncommon congenital hypomelanosis of the skin that is often characterized as being nonprogressive and having serrated borders. It needs to be distinguished from other hypopigmented skin conditions such as nevus anemicus, hypomelanosis of Ito, Fitzpatrick patches (ash leaf spots) of tuberous sclerosis, vitiligo, indeterminate leprosy, and pigment demarcation lines. Treatment may be desired for aesthetic and possible psychosocial considerations. We review and update knowledge about ND and its simulants.