Association between cytokine levels and disease relapse in newly diagnosed childhood-onset primary nephrotic syndrome.

OBJECTIVE: Although most pediatric patients with primary nephrotic syndrome (PNS) are steroid-sensitive, some develop steroid dependence and experience disease relapse. Therefore, identifying risk factors associated with PNS relapse is clinically important. METHODS: This retrospective study included 74 children with newly diagnosed PNS and 39 healthy children as controls. Patients with PNS were classified into relapse and non-relapse groups according to whether relapse occurred within 6 months after disease onset. Serum cytokine levels and peripheral blood lymphocyte subsets were measured using enzyme-linked immunosorbent assays and flow cytometry, respectively. RESULTS: Demographic characteristics and laboratory findings did not differ significantly between male and female children with PNS. Compared with healthy controls, patients with PNS exhibited abnormal white blood cell and platelet counts, an elevated erythrocyte sedimentation rate, and increased absolute counts of peripheral blood lymphocyte subsets (all P < 0.05). The interleukin-1β (IL-1β) positivity rate was significantly higher in the relapse group than in the non-relapse group (P < 0.05). IL-1β positivity was significantly associated with an increased risk of disease relapse (odds ratio = 9.727, 95% confidence interval: 1.650-102.224, P = 0.012; area under the curve = 0.591; Brier score = 0.177). PNS relapse was positively correlated with increased IL-1β levels (r = 0.321, P = 0.005). CONCLUSIONS: IL-1β positivity is associated with relapse within 6 months of onset in children with newly diagnosed PNS. Further studies are required to validate this association and elucidate the underlying mechanisms.