Background: Vitiligo is a chronic autoimmune disorder that significantly impacts psychological well-being and quality of life. Interleukin-38 (IL-38), a cytokine with immunomodulatory properties, may influence the disease's pathogenesis. Narrowband ultraviolet B (NB-UVB) phototherapy, a standard vitiligo treatment, is known to modulate immune responses, but its effect on IL-38 remains underexplored.
Objectives: To assess serum IL-38 levels in vitiligo patients, evaluate their correlation with disease severity, and investigate the impact of NB-UVB therapy on IL-38 and clinical outcomes.
Patients and Methods: This case-control study enrolled 30 patients diagnosed with non-segmental vitiligo, alongside 15 healthy controls matched for age and sex. Serum IL-38 levels were measured using ELISA before and after three months of NB-UVB phototherapy. Disease severity was assessed using Vitiligo Area Scoring Index (VASI), Vitiligo Disease Activity (VIDA), and Dermatology Life Quality Index (DLQI).
Results: Baseline IL-38 levels were significantly higher in vitiligo patients compared to controls (median = 30.27 vs 15.14 pg/ml; P < 0.001). Post-treatment, IL-38 levels decreased significantly (median = 23.2 pg/ml; P= 0.003). VASI scores improved from a median of 5 to 2 (P < 0.001). IL-38 levels positively correlated with VASI (r = 0.511; P = 0.004), VIDA (r = 0.419; P = 0.021), and DLQI (r = 0.434; P = 0.017). Logistic regression indicated that each unit increase in IL-38 increased vitiligo risk by 24% (OR = 1.243; P = 0.002).
Conclusion: IL-38 levels correlate with vitiligo severity and decrease with NB-UVB therapy, suggesting its potential role as a biomarker and therapeutic target.