Association of Kidney Biopsy Findings With Short- and Medium-Term Outcomes in Children With Moderate-to-Severe Iga Vasculitis Nephritis

Abstract Assessing the initial severity of immunoglobulin A vasculitis nephritis (IgAV-N) is challenging important due to its determining effect on kidney management and outcomes. This study paper aims to describe describes a multicentre paediatric multicenter pediatric cohort of IgAV-N patients and discusses whilst investigating the relationships among between clinical presentation, histological features, and kidney outcome. A cohort consisting of 170 children requiring early kidney with biopsy because of IgAV-N, which was diagnosed between 2007 and 2017, was assessed including 27% of children with nephrotic syndrome (NS). One-quarter of the cohort (27%) presented with initial nephrotic syndrome (NS). Kidney biopsy revealed International Study of Kidney Disease (ISKDC) grade II or grade III in 83% of cases. An International Study of Kidney Disease (ISKDC) grade II or grade III was revealed through kidney biopsy in 83% of cases. Endocapillary proliferation was were observed in 73% of patients, and chronic lesions were observed in 25%of patients. Data analysis demonstrated showed a significant association between clinical severity (NS at onset and histological findings such asendocapillary proliferation and cellular crescents. After a median follow-up of 21 months (IQR 12-39), 30% of patients had persistent kidney impairment (proteinuria or decreased eGFR. WorseAt the end of follow-up, kidney outcome impairment was significantly associated more often observed in patients with NS at onset and those with cellular crescents and chronic lesions on initial kidney biopsy.Conclusions: This study highlights the relationship between the clinical and histological presentation of IgAV-N and the factors that affect kidney outcome. The ISKDC classification may be improved by including lesions that are more discriminating for disease severity and prognosis.