Background Until now, segmental vitiligo has been considered as a stable entity and mixed vitiligo, the association of segmental and nonsegmental vitiligo, has been reported rarely.
Objectives The aim of this study was to search for factors associated with the generalization of vitiligo in patients with segmental vitiligo.
Patients and methods This was a prospective observational study conducted in the vitiligo clinic of the Department of Dermatology of Bordeaux, France. The Vitiligo European Task Force questionnaire was completed for each patient attending the clinic with a confirmed diagnosis of segmental vitiligo after exclusion of other forms of vitiligo (focal, mucosal, not classifiable.) Thyroid function and antithyroid antibodies were screened if not obtained in the previous year.
Results One hundred and twenty-seven patients were recruited: 101 had segmental vitiligo and 26 had segmental vitiligo that evolved into mixed vitiligo; 56 were male and 71 were female. Most patients had onset of segmental vitiligo before the age of 18. When conducting multivariate analysis, we found the following to be independent factors associated with the evolution of patients’ disease from segmental vitiligo to mixed vitiligo: initial percentage of body surface involvement of the segment > 1% [odds ratio (OR) 15·14, P = 0·002], the presence of halo naevi (OR 24·82, P = 0·0001) and leukotrichia (OR 25·73, P = 0·0009).
Conclusions Halo naevi association and leukotrichia at first consultation in segmental vitiligo are risk factors for the progression of segmental vitiligo to mixed vitiligo. In addition, this progression of segmental vitiligo to mixed vitiligo carries a stronger link if initial segmental involvement is situated on the trunk.