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.

Hematological Markers in Children and Adults with Atopic Dermatitis: A Retrospective Cohort Study.

INTRODUCTION: Atopic dermatitis (AD) is a common chronic skin disease with an inflammatory pathophysiology that includes the activation of the innate and adaptive immune systems. We aimed to investigate the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), eosinophil-to-lymphocyte ratio (ELR), and eosinophil-to-neutrophil ratio (ENR) in AD patients, according to age and disease severity. METHODS: This is a retrospective, population-based cohort study conducted between the years 2005 and 2020, comparing hematological markers of AD patients and sex-age-ethnicity-matched controls. AD patients were further divided by age and disease severity (mild, moderate-to-severe AD). We created a decision tree to predict moderate-severe AD. RESULTS: A total of 13,928 patients with AD were included in this study: 6,828 adults and 7,100 children, with 13,548 controls. NLR, PLR, and ELR were lower in children compared to adults (p values <0.001). NLR, PLR, ELR, and ENR were increased in moderate-severe AD patients compared to mild AD patients (p values <0.001). PLR, ELR, and ENR were increased in AD patients versus controls (p values <0.001), with an additional increase in the NLR of moderate-to-severe AD patients. Patients with an ELR <0.21, a PLR >161, and ENR ≤0.016 should be considered high risk for developing severe AD, as well as patients with an ELR >0.21 and age at diagnosis <30 or age >30 years and mean platelet volume ≤9. CONCLUSION: Hematological ratios were significantly higher in moderate-to-severe AD patients, compared to mild AD patients. Hematological markers were lower in children with AD compared to adults, except for ENR, likely reflecting age-related changes in blood count parameters. These markers can assist in the management and follow-up of AD patients.