The Role of Cytokines and Chemokines as Biomarkers of Disease Activity in Idiopathic Nephrotic Syndrome in Children.

(1) This study investigates the association of plasma concentrations of various cytokines and chemokines with the disease activity of idiopathic nephrotic syndrome (INS) in children in Slovenia. (2) In a prospective single-center study lasting 18 months, we took sequential plasma samples from children with INS at disease onset or relapse (prior to corticosteroid (CS) therapy), at remission, and after discontinuation of CS therapy. The Olink(®)Target 48 Cytokine Panel was applied to analyze 45 analytes in the plasma samples, adhering to the manufacturer's protocol. We performed a statistical analysis with a paired samples analysis with a t-test as well as with a non-parametric Wilcoxon correction test. (3) We included 18 pediatric patients with INS in the study. We demonstrated statistically significant differences in the concentrations of CSF1, IL4, FLT3LG, CCL19, and MMP12 in the patients at disease onset or relapse compared to those in remission, differences in the concentrations of CSF1 and IL17F in the patients at disease onset or relapse compared to those in remission after CS treatment, and differences in the concentrations of CCL19, MMP12, and CCL13 in the patients in remission compared to those in remission after CS treatment. (4) The findings support potential roles of certain cytokines and chemokines, especially CSF1, CCL19, and MMP12, in influencing the disease activity of INS.