الفهرس 
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Abstract
Vitiligo is a primary acquired pigmentary disorder characterized by the presence of well-circumscribed, milky-white macules on the skin and mucous membranes due to loss of functioning melanocytes from the involved areas (Nicolaidou and Katsambas , 2014). It occurs worldwide with an estimated prevalence of 0.5–2% in most populations )Krüger and Schallreuter ,2012). In almost half of patients, vitiligo starts before the age of 20 yr, and males and females are affected with approximately equal frequency (Picardo and Taiieb ,2010).
Vitiligo is a multifactorial polygenic disorder with a complex pathogenesis, linked with both genetic and non-genetic factors. The exact etiology of vitiligo remains obscure.Theories regarding loss of melanocytes are based on autoimmune, cytotoxic, oxidant–antioxidant and neural mechanisms (Laddha et al.,2013)
Estrogens have prominent effects on immune functions and both ERα and ERβ are expressed in immune cells (Yakimchuk et al.,2013). It seems that estrogen may indeed be associated with a predisposition for autoimmune disorders in men (Doukas et al., 2012) and play important roles in pathophysiology of autoimmune rheumatic diseases (Cutolo et al.,2011).