Prevalence of Autoimmune Disorder in Patients with Vitiligo

Vitiligo is the most common acquired pigmentation disorder; which manifests as depigmented patches of skin; rarely mucosa and hair. The prevalence of vitiligo in different races is around 0.1-2%.Many factors have been proposed as possible etiologic factor including genetics, free radicals, autoimmune reactions, melanocytic growth factors deficiency, melatonic destruction. Here we studied the association between vitiligo and autoimmune diseases. In this prospective study 86 patients with vitiligo were questioned about the location of vitiligo, family history, treatment and therapeutic response. All patients were examined both clinically and with laboratory tests to detect the presence of autoimmune disorders including autoimmune thyroid disease, pernicious anemia, insulin dependent diabetes, systemic lupus erythematic (SLE) and Addison disease. The laboratory tests including TSH, T3, T4, Hg, Na, ANA, ESR and K were performed. We compared the prevalence of autoimmune disorder in vitiligo patients with that in a group of age – and gender-matched normal population. Average age of disease onset was 21.811 years; 61% of patients were female and 39% were male. The most common locations of vitiligo were hands (33.7%) and face (32.1%). The most common pattern of onset was vulgaris type (40%). Nearly one – fourth of patients had a positive family history of vitiligo. Prevalence of thyroid disorders in vitiligo patients and control group was 21.1% and 7%, respectively. The difference was statistically significant (P=0.008). Response to treatment in patients with positive family history was 20%, comparing with 37% in sporadic cases (P=0.01). The most common autoimmune disorder in patient with vitiligo was hypothyroidism (clinical and subclinical). Family history had a poor prognostic effect on response to therapy.