New Insights in Mixed Vitiligo: Initial Non Segmental Vitiligo can precede the Onset of Segmental Vitiligo (Cases Report and Review of Theories)

Abstract

Recently, mixed vitiligo (MV) was defined by Mulekar as the association of segmental vitiligo (SV) and nonsegmental vitiligo (NSV) in the same patient. Until now, SV and generalized NSV were considered to be separate entities with a different distribution (unilateral or bilateral). Generalized vitiligo seemed to be more frequently associated with other autoimmune diseases than SV. From the pathophysiological standpoint, it was hypothesized that NSV was an autoimmune disease, while SV may result of a sympathetic dysfunction. The first pediatric case of SV associated with NSV was reported in 2003 and 36 other observations were subsequently reported. In all these cases, segmental involvement associated usually in a second step with the onset of bilateral vitiligo patches. In this article, we describe, for the first time, two atypical cases of mixed vitiligo in which NSV involvement preceded the onset of SV. In the light of these remarkable cases, different possible aetiopathogenetic mechanisms of MV are discussed which may provide new insights into the pathogenesis of vitiligo.