Immunohistochemical expression of melatonin in nonsegmental vitiligo and its role in the pathogenesis: a case–control study

[摘要] Background  Vitiligo is the most common skin depigmentation disorder. Melatonin is a hormone that affects melanogenesis and pigmentation. The possible role of melatonin in the pathogenesis of vitiligo remains unclear. Objective  The aim was to estimate immunohistochemical expression of melatonin in lesional and nonlesional skin of patients with nonsegmental vitiligo in comparison to healthy controls in order to detect the possible variable expression of melatonin and its possible role in the pathogenesis of vitiligo. Patients and methods  In all, 40 lesional and 40 nonlesional skin biopsies from 40 patients with nonsegmental vitiligo and 40 healthy control biopsies were included. Immunohistochemistry of melatonin expression in skin biopsies was performed. Vitiligo area scoring index score was used to assess vitiligo severity. Results  Melatonin expression was significantly lower in lesional and nonlesional skin of vitiligo patients (P<0.001) with almost the same level in significant concordance (κ, P=0.7, 0.005), as compared with controls. This lower melatonin expression was evident with as the age progresses (P<0.001) and not related to vitiligo area scoring index scores and family history (P0.05) of vitiligo. Conclusion  Our results showed a significant lower melatonin expression in the lesional and non-lesional skin of vitiligo patients than controls. Melatonin deficiency in vitiligo skin lesions was almost equal in vitiligo-free areas, suggesting a significant role for melatonin hormone deficiency in the pathogenesis of vitiligo.

[学科分类] 皮肤病学

[关键词] immunohistochemistry;melatonin;pathogenesis;vitiligo