Definition and Characteristics
Vitiligo is an acquired, idiopathic hypomelanotic disorder in which a progressive loss of melanocytes from the epidermis and hair follicles results in well-circumscribed cutaneous depigmented macules .
Vitiligo is the most common pigmentary disorder worldwide. The prevalence is 0.5-2% without a predilection for age, sex or race.
Several candidate genes have been proposed for vitiligo susceptibility, including genes important for melanin biosynthesis, response to oxidative stress and/or regulation of autoimmunity [2,3]. However, none of these vitiligo susceptibility genes has yet been identified. Case-control studies examining human leukocyte antigens (HLA) have shown a positive association with HLA DR4 and a negative association with HLA DR3 .
Molecular and Systemic Pathophysiology
The mechanisms leading to the loss of pigment cells are not yet fully understood. Melanocytes could be destroyed by necrosis, apoptosis