1 - Nephrology Unit, Hospital D. Estefânia, Central Lisbon University Hospital Centre, Lisbon, Portugal
- 56th Annual Meeting of the European Society for Paediatric Nephrology, 24-26/9/2024, Valência, Espanha, Pitch presentation
- Resumo publicado em: Pediatr Nephrol 2024;39(Suppl 1):S245.
Abstract:
Aims/Purpose: IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis, with a highly variable clinical presentation and prognosis. We aimed to compare real-world kidney outcomes in a cohort of children with IgAN with the predicted kidney outcomes at the time of kidney biopsy based on the International IgAN Prediction Tool adapted for children (IIgAN-PT).
Methods: Single-centre longitudinal retrospective study of patients aged between 0 and 18 years who had a biopsy-proven IgAN diagnosis between 2010 and 2022. IgA vasculitis and secondary IgAN cases were excluded. Demographic, clinical, laboratory, and histological variables were analysed. The IIgAN-PT score was calculated for each patient according to the follow-up time in the study. The primary outcome was a composite of ≥30% decrease in eGFR or progression to CKD stage 5. Secondary outcomes were a new onset of albuminuria/proteinuria and any reduction in eGFR from baseline.
Results: In our cohort of 23 patients, 13 (57%) were male, and the median age at biopsy was 13.8 years (interquartile range (IQR) 9.6-16.3). The MEST-C score was M1 in 20 (87%), E1 in 5 (22%), S1 in 9 (39%), T1/2 in 3 (13%), and C1 in 6 (26%). Based on the IIgAN-PT score at the biopsy, the median predicted risk of ≥30% decline in eGFR or progression to CKD 5 accounting for each individual’s follow-up time was 6.5% (IQR 4.5-8.6). After a median follow-up of 3.1 years (IQR 1.7-7.3), six (26.1%) patients met the primary outcome, including one (4.3%) patient who had received a kidney transplant. Two (9%) patients developed de novo albuminuria/proteinuria, and the eGFR decreased in 13 (57%) patients. The median annual decline in eGFR was 5.6 ml/min/1.73m2 (IQR 1.98-17.4).
Conclusions: In our cohort, a decrease in eGFR ≥30% or progression to CKD 5 occurred four times more frequently than expected at the time of biopsy. This disparity could be at least partially attributed to different duration of symptoms/signs of IgAN before biopsy. Despite our small sample size and relatively short follow-up, small-scale reproducibility studies such as ours may provide insights to improve the study design of larger studies conducted to improve the prediction ability of this tool across different clinical settings.
Keywords: IgA nephropathy, IIgAN-PT, MEST-C score