Introduction: Vitiligo is an acquired cutaneous disorder characterized by progressive and selective destruction of melanocytes from the epidermis. Autoimmunity is strongly implicated in its pathogenesis. The destruction of melanocytes has a correlation with the peripheral blood lymphocyte imbalance mainly including Cytotoxic T cells (CD8+cells) and Helper T cells (CD4+cells). The progression of vitiligo is associated with higher CD8+ counts and lower CD4+ counts thus, altering CD4+: CD8+ ratio.
Aim: To evaluate the clinically suspected cases of vitiligo histopathologically and histochemically and to establish the co-relation of autoimmunity with the flow cytometric analysis of CD8+ and CD4+ lymphocyte counts.
Materials and methods: In this study, 40 patients with proven vitiligo were taken. The destruction of melanocytes was confirmed by Haematoxylin & Eosin (H & E) and by histochemical stains using Dihydroxyphenylacetic Acid (DOPA) reaction. Blood sample from these vitiligo patients and 10 control subjects was taken. Flow Cytometry was used for the determination of CD8+ and CD4+ counts in the vitiligo patients and control subjects. Then CD4+: CD8+ ratio was calculated and comparison between vitiligo patients and control subjects was done. T-test was used for the statistical analysis.
Results: There was statistically significant decrease in CD4+: CD8+ ratio. CD4+: CD8+ ratio was decreased in 57.5% cases of vitiligo with increase in CD8+ counts and decreased CD4+ counts.
Conclusion: It was concluded from this study that cellular immunity might have a role to play in the pathogenesis of vitiligo causing the destruction of melanocytes.
Keywords: Cellular; Depigmentation; Immunity; Melanin.