Decreased Neutrophil-to-lymphocyte Ratio in Patients with Vitiligo: National Data Analysis.

Vitiligo is characterized by depigmented skin lesions involving melanocyte defects and immune dysregulation. Haematological markers like neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been explored in various skin disorders. Given vitiligo's proposed pathogenesis, we hypothesized differences in NLR and PLR in vitiligo patients compared to controls. In a national retrospective cohort study (2005-2020) in Israel, blood count data from patients diagnosed with vitiligo (ICD-10 codes) were analysed, excluding patients with recent infections, surgeries, or malignancies. Controls matched for age and sex were selected. Sub-analyses examined age groups, treatment type, and matched controls. Children (n = 3,796) and adults (n = 38,608) with vitiligo showed significant differences in gender distribution, cell counts, and ratios. Vitiligo patients (n = 38,358) exhibited lower NLR, decreased neutrophils and platelets, and increased lymphocytes compared with controls. Non-systemically treated vitiligo patients (n = 33,871) displayed lower NLR and neutrophils compared with matched controls. Systemically treated vitiligo patients (n = 4,487) showed lower NLR, higher PLR, and reduced lymphocytes. Logistic regression identified associations between increased lymphocyte and platelet counts and being systemically treated. This study highlights significant haematological differences in vitiligo patients, emphasizing the potential utility of NLR as an accessible tool for vitiligo assessment. Further investigations are warranted to elucidate the roles of neutrophils and lymphocytes in vitiligo pathogenesis.