3Pathology, Medical School, Shiraz University of Medical Sciences, Shiraz-Iran.
Background: Vitiligo is a dermatological disorder of unknown etiology with a common incidence in southern Iran. Presence of autoantibodies to melanocyte antigens suggested an autoimmune basis of the disease. Objective: In this study, the presence of rheumatoid factor (RF) in sera and skin biopsies of vitiligo patients was investigated. Methods: The presence of RF in sera of 35 vitiligo and 32 normal individuals was assessed by an indirect ELISA assay. In addition, the presence of IgM, IgG, and IgA immunoglobulins in the biopsy lesions of patients was also investigated by Immunoperoxidase test. Results: IgM-RF and IgA-RF were detected in sera of 50% and 20% of patients, respectively. Five out of 35 (15%) revealed to produce both IgM and IgA rheumatoid factors. The rheumatoid factor activity of the deposited immunoglobulins at the site of lesion was confirmed by direct immunoperoxidase test. Conclusion: The presence of rheumatoid factors as non organ-specific autoantibodies in vitiligo provides further evidence for the autoimmune etiology of the disease and its pathological importance remains to be elucidated.