Prognosis and predictive factors in pediatric IgA nephropathy

Abstract Background IgA nephropathy (IgAN) is a common glomerular disease in children that may progress to chronic kidney disease (CKD) and kidney failure. Identifying reliable prognostic markers is important for guiding clinical management. This study investigated independent predictors of poor prognosis in pediatric IgAN and their impact on eGFR slope, as well as the dynamic patterns of complete kidney remission and relapse, predictive factors associated with remission, and the influence of remission on poor prognosis. Methods A retrospective cohort study of 224 children (aged 3–18 years) with biopsy-proven IgAN and ≥ 3 years of follow-up was enrolled. Poor prognosis was defined as persistent eGFR < 90 mL/min/1.73 m 2 for ≥ 3 months. Multivariate logistic regression, receiver operating characteristic (ROC) curve analysis, and linear mixed-effects model were used to identify predictive factors and evaluate eGFR slope. Complete kidney remission was defined as the absence of hematuria and proteinuria with eGFR ≥ 90 mL/min/1.73 m 2 for ≥ 1 year. Cumulative incidence function and Fine-Gray competing risk regression model were applied to analyze remission dynamic patterns. Results Over a median follow-up of 5.41 years, 12.05% reached the poor prognosis. Independent risk factors included male sex, older age at biopsy, Oxford classification E1 and S1 lesions, absence of gross hematuria, and no remission of proteinuria during follow-up, while higher birth weight was protective. eGFR slope was influenced by age at biopsy, gross hematuria and proteinuria remission status during follow-up. Complete kidney remission occurred in 70.98%, with a recurrence rate of 60.38%. Predictors of complete kidney remission included antecedent infection, kidney IgM deposition of 2 + , elevated serum IgM, increased pathological casts count, and prednisone treatment, while prolonged disease duration before biopsy and higher tubular casts count were risk factors. Group comparisons and logistic regression analysis showed no significant associations between kidney remission and poor. Conclusions Pediatric IgAN shows slow disease progression over 5 years. Despite high complete kidney remission rates, recurrence remains common. These findings support extended follow-up and improved predictive models. Graphical abstract