Abstract
Introduction: Studies on Lipocalin-2, Serum Amyloid A, and Calprotectin have established their relevance to autoimmune and inflammatory conditions, showing their contributions to the etiology and pathogenesis of vitiligo. To determine the serum Lipocalin-2, Serum Amyloid A, and serum Calprotectin levels in patients with vitiligo.
Methods: A case-control study was conducted at the Dermatology Department, Baghdad Teaching Hospital, Baghdad, Iraq (November 2025 – April 2026), enrolling 70 patients with vitiligo and 50 healthy controls. Serum Lipocalin-2 (LCN2), Calprotectin (CAL), and Serum Amyloid A-4 (SAA4) were quantified using BT Laboratory sandwich ELISA kits (Catalog Nos. E1429Hu, E4010Hu, E6165Hu). Statistical analyses included an independent t-test, a one-way ANOVA with Duncan’s post hoc test, Spearman’s rank correlation, and ROC curve analysis, all performed in IBM SPSS version 27.
Results: Serum Lipocalin-2 was significantly elevated in vitiligo patients compared to controls (718.05±66.844 vs. 434.07±28.805 ng/L; P<0.001). Calprotectin was likewise markedly higher in patients (82.88±9.301 vs. 42.51±6.366 ng/mL; P=0.001). Serum Amyloid A was also significantly higher in patients than controls (80.62±9.753 vs. 59.45±1.563 ng/L; P=0.035). Calprotectin achieved the highest AUC (0.892; 95% CI: 0.831–0.953), with sensitivity of 85.5% and specificity of 84.0%. Lipocalin-2 demonstrated AUC=0.729, sensitivity 87.0%, specificity 67.0%.
Conclusion: Serum concentrations of Lipocalin-2, Serum Amyloid A, and Calprotectin were higher in patients with vitiligo than in healthy controls. This finding supports the presence of an active inflammatory state in patients with vitiligo. Calprotectin was the strongest inflammatory marker in this study. The three inflammatory markers were positively correlated, indicating they are linked to a common inflammatory pathway in vitiligo.