Bulgarian Society of Dermatology

Journal of Clinical & Experimental Dermatology Research

Treatment of Non-Segmental Vitiligo with Narrowband UVB Phototherapy (311 Nm): Clinical Efficacy and Mechanisms of Action

Abstract

Author(s): Diana Proshutinskaia, Vladimir Volnukhin and Oksana Katunina

Objective: To estimate efficacy of narrowband UVB phototherapy (311 nm) in non-segmental vitiligo and its effect on subpopulations of T-cells and dendritic cells in vitiligo lesions.

Methods: 56 patients with progressive non-segmental vitiligo underwent narrowband UVB phototherapy (311 nm). 11 patients had biopsies before and after therapy from lesional (depigmentation area), marginal, and perilesional skin for immunohistochemical studies of CD4+, CD8+, CD1a+ and CD83+ cells in epidermis and derma.

Results: Median number of UVB procedures per course was 71, median total radiation dose-91.8 J/cm2, median percent of repigmentation-49%. Repigmentation of >25% of the affected area was reached in 67.9% of patients and repigmentation of 76-100% in 19.6% . VIDA index decreased from 2 to 1 post-treatment (P<0.035).

In a subgroup who underwent immunohistochemical studies median number of UVB procedures per course was 88, median total dose of radiation-140.2 J/cm2, and median percent of repigmentation-50%. Significant activation of T-cellular immune reactions was found in lesions before treatment. There was a statistically significant increase in CD8+ lymphocytes and CD1a+ dendritic cells in marginal and perilesional normally pigmented skin in epidermis. There was an increase in CD4+ and CD8+ lymphocytes and CD83+ dendritic cells in all three zones in derma. Normalization of CD8+ and CD1+ cells in epidermis of the affected skin was observed post-treatment. There was only partial reduction of CD4+, CD8+ and CD1+ cells in dermis.

Conclusions: Narrowband UVB phototherapy (311 nm) is an effective method of treatment of nonsegmental vitiligo. T-lymphocytes and Langerhans cells play a critical immunoregulatory role in narrowband UVB phototherapy (311 nm)-induced immune suppression. Lack of full normalization of immunological parameters in the skin after treatment indicates a need for optimization of narrowband UVB phototherapy (311 nm): conduction of longer courses including 150-200 procedures, or combinations of this treatment with immunosuppressive drugs.