Dermoscopy: a useful auxiliary tool in the diagnosis of type 1 segmental Darier's disease.

Type 1 segmental Darier's disease is a blaschkolinear variant of Darier's disease resulting from a postzygotic mosaicism. Since it usually lacks diagnostic clues typical of the generalized form, including positive family history of the disease, nail and mucosal abnormalities, and/or acral involvement, its distinction from other acquired inflammatory blaschkolinear dermatoses may often be quite challenging, thus requiring histopathological examination to reach a definitive diagnosis. We report a case of type 1 segmental Darier's disease with its dermoscopic findings in order to show the usefulness of dermoscopy in assisting the noninvasive identification of this condition.