SummarySegmental vitiligo is often ascribed to the neurogenic theory of melanocyte destruction, although data about the initial etiopathological events are scarce. Clinical, histopathological and T-cell phenotypic analyses were performed during the early onset of a segmental vitiligo lesion in a patient with associated halo nevi. Histopathological analysis revealed a lymphocytic infiltrate, mainly composed of CD8 + T-cells and some CD4 + T-cells around the dermo-epidermal junction. Flow cytometry analysis of resident T-cells revealed a clear enrichment of pro-inflammatory IFN-c producing CD8 + T-cells in lesional skin compared to the non-lesional skin. Using human leukocyte antigen-peptide tetramers (MART-1, tyrosinase, gp100), increased numbers of T cells, recognizing melanocyte antigens were found in segmental vitiligo lesional skin, as compared with the non-lesional skin and the blood. Our findings indicate that a CD8 + melanocyte specific T cell-mediated immune response, as observed in generalized vitiligo, also plays a role in segmental vitiligo with associated halo nevi.