A hairy paradox: congenital triangular alopecia with a central hair tuft.

Congenital triangular alopecia (CTA) is a developmental anomaly characterized by a bald patch involving the temporal region on one or, more rarely, both sides. We report 5 patients with CTA showing a central island of short hair that was categorized as terminal hair both macroscopically and microscopically. The cause of this paradoxical phenomenon is unknown.