| Background Vitiligo (OMIM: #193200) is an acquired, pigmentary disordercharacterized by a loss of melanocytes resulting in white spots. It affects 0.1% to 2% ofthe population worldwide.Vitiligo occurs in all races, affects both sexes equally, candevelop at any age,although the first two decades are more common. The pathogenesisof vitiligo is unknown, but genetic factors are thought to be involve. To date, there is nouniversally accepted standardized classification system for vitiligo. Vitiligo can beclassified into segmental vitiligo and nonsegmental vitiligo vitiligo that appeared tofollowed a dermatomal distribution was considered to represent segmental vitiligo;nonsegmental vitiligo compromised all other types of vitiligo,such as localized,generalized, universal and acrofacial.Objective To discribe the clinical and epidemiological features of segmental vitiligoin Chinese patients,and to explore the roles of gender and genetic factor in clinicalphenotypes of segmental vitiligo patients.Also,differences in disease characteristicscompared with segmental vitiligo and nonsegmental vitiligo are discussed.Methods We collected eligible data from 3143 patients with vitiligo by a uniformquestionnaire, of which 311 segmental vitiligo and 2832 nonsegmental vitiligo. All thedata were inputted into a database set up by EpiData 3.0 package. After propertransformation, the data were statistically analyzed by statistic package of social science(SPSS, version 13.0).Results①The mean age of onset was 15.45±10.91 years old with a range from 1 to70 years.77.2% of the patients were affected before 20 years. The predilection site wasthe face. The common season of onset was summer. More than 50% of the patients had causative factors.②No significant difference was identified with respect to age ofonset, season of onset, disease severity, associated environmental factors between male and female patients.But female patients affect chest and abdomen(x~2=4.434, P=0.035), and back(x~2=4.734, P=0.030) more frequently than male patients.③9.0% segmentalvitiligo patients have a positive family history. There is no significant difference in ageof onset, disease severity, affected sites and season of onset between familial andsporadic segmental vitiligo. Compared with sporadic segmental vitiligo, more familialpatients have moisture history (x~2=9.142, P=0.002).④Compared with nonsegmentalvitiligo,segmengtal vitiligo had an earlier age of onset and significantly lower incidenceof a positive family history, and was rarely associated with halo nevus and otherautoimmune diseases.Conclusions①From the analysis of our data, segmental vitiligo in chinese patientsare characterized by a younger age of onset and weaker gender predominance. Butgender may have effect on affected sites.②Our findings also indicated that geneticfactor has no strong influence on the phenotypes of segmental vitiligo.③The clinicalcharacteristics of segmental vitiligo differ from those of nonsegmental vitiligo,whichmay result from different pathogenesis. |
