Clinical features and course of type A and type B vitiligo

Abstract

Four hundred and eighty one cases of vitiligo (acquired idiopathic depigmentation) were studied clinically. They were divided into two types, type B, in which depigmented patches are confined to a definite dermatome in the same manner as herpes zoster, and type A, which included all cases of vitiligo not classified as type B. The ratio of type A:type B was approximately 3:I. Onset of type A vitiligo could occur at any age, whereas type B generally affected the young. The activity of type B vitiligo usually ceased after one year, following rapid spread over the particular dermatomal area. However, in type A vitiligo new depigmented patches continued to appear throughout the patients' lives. Association with halo naevus and Köbner's phenomenon were observed exclusively in type A. Association with diseases with a proven or suggested allergic or immunological aetiology was more often found in type A. These findings support our hypothesis that type A and type B vitiligo have a different pathogenesis and that autoimmune mechanisms play a role only in type A.