Trichotillomania in connection with alopecia areata.

Alopecia areata and trichotillomania present the most frequent causes of circumscribed hair loss in children. The connection between trichotillomania and alopecia areata has confused former observers. It may result from scratching at the site of alopecia areata that is symptomatic with pruritus, initiating a habit-forming behavior, or patients with a mental predisposition may artificially prolong the disfigurement as the hair on the bald patches of alopecia areata regrows. We have seen the concomitant occurrence of trichotillomania and alopecia areata in a 13-year-old boy, and confirmed the diagnosis by results of histopathologic examination. With regard to pathogenesis and prognosis, the differentiation of trichotillomania in connection with alopecia areata from the more common patterns of temporary localized childhood trichotillomania and severe adult trichotillomania is suggested.