Sketched hairs in eyebrow trichotillomania.

Abstract

Dermoscopy is a useful aid in hair diseases and in particular in differentiating alopecia areata (AA) from trichotillomania (T). The most important dermoscopic marker of AA is the exclamation mark hair, that of T the broken hair; both markers reflect the pathogenesis of the two disorders (1). However, exclamation mark-like hair has been described in T and some signs such as vellus hair, dystrophic hair, yellow dots are present both in AA and in T (2). In the actual report we describe a new dermoscopic sign of T, the sketched hair, which is reminiscent of acquired pseudomoniletrix and could be due to repeated traumas but insufficient to break the hair. However, dermoscopy should not induce dermatologists to forget the diagnostic importance in differentiating AA from T of the family and personal history, shape and distribution of patches, presence or otherwise of hair of different length inside the patch and pull test.