Since abnormal keratinocyte (KC) proliferation and differentiation as well as defective E cadherin expression were reported in vitiligo lesions, the investigators set to study the potential efficacy of combining Retinoids, which are known to improve KC proliferation and differentiation and increase the expression of adhesion molecules, with narrowband UVB in the treatment of vitiligo.

• 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.

Inclusion Criteria:

• Patients with generalized non-segmental vitiligo (25%-75%)
• Males, postmenopausal females and premenopausal females not planning to get pregnant during the period of treatment and after 2 years from the end of treatment.
• Age more than 18 years.

Exclusion Criteria:

• Children ˂ 18 years old
• Pregnant females
• Premenopausal females planning to get pregnant within the period of treatment or within 2 years after.
• Patients receiving treatment for vitiligo within the past 2 months.
• Patients with abnormal liver profile
• Patients with abnormal lipid profile
• Patients with associated photosensitive disorders
• Patients having associated skin diseases other than vitiligo
• Cataract and aphakia
• High cumulative dose from previous sessions of narrowband ˃ 200-300 session