Combined Effect of Acitretin and Narrow Band Ultraviolet B on Vitiligo Repigmentation

• Twenty patients with generalized vitiligo will be included in this study. All patients will be subjected to: * Clinical evaluation: * An informed written consent. * History taking include age, previous treatment, disease activity * Clinical examination including Vitiligo Area Scoring Index (VASI) and Vitiligo Disease Activity Score (VIDA) * Photography (before starting the treatment and every 2 weeks till the end of the study) Laboratory evaluation: * 2 mm punch skin biopsies will be taken from vitiligo patients, 1 from lesional and the other from perilesional skin before treatment. * The patients will be randomly assigned to two groups: Group A: patients will receive three NB-UVB sessions per week for 48 sessions. Group B: patients will receive three NB-UVB sessions per week for 48 sessions combined with acitretin in a dose of 0.3mg/kg/day daily. * Controls: 20 individuals age and sex matched will be biopsied from the skin of their abdominoplasty surgery. * Another two 2 mm punch skin biopsies will be taken from lesional and perilesional skin at the onset of repigmentation if repigmentation starts before completion of the 48 treatment session or after completion of the treatment period if repigmentation does not occur. * .All biopsies from patients and controls will be stained Immunohistochemically by anti-E cadherin antibody.