1 - Paediatric Nephrology Unit, Hospital Dona Estefânia, Central Lisbon University Hospital Centre, Lisbon, Portugal
2 - Serviço de Pediatria, Centro Hospitalar Barreiro-Montijo, Montijo, Portugal
3 - Centro da Criança e do Adolescente, Hospital CUF Descobertas, Lisbon, Portugal
- VII Congresso Hispano-Português de Nefrologia Pediátrica e XLVI Congreso Español de Nefrologia Pediátrica. 18 e 19 de Maio de 2023, NOVA Medical School, Lisboa. Comunicação oral longa.
- Prémio para a 2ª melhor comunicação oral portuguesa.
Introduction: Oxford classification of IgA nephropathy (IgAN) defines histologic criteria (MEST-C) that provide prognostic information based on kidney biopsy. The International IgAN Prediction Tool (IIgAN-PT) predicts, at the time of kidney biopsy, the risk of a 50% decline in estimated glomerular filtration (eGFR) or progression to end-stage kidney disease (ESKD).
Objectives: We aimed to correlate MEST-C and IIgAN-PT scores at the time of kidney biopsy with renal outcomes in a pediatric cohort of IgAN.
Methods: Retrospective cohort study of paediatric patients with biopsy-proven IgAN diagnosed between 2010 and 2022. Demographic, clinical, laboratorial, and histologic variables were analysed. The primary outcome was a composite of eGFR loss, ESKD, or incident proteinuria.
Results: MEST-C was available for 23 patients (52% were male). Median age at biopsy was 13.8 years (interquartile range (IQR) 9.6;16.3). The MEST-C scores were M1-87%, E1-22%, S1-39%, T1/2-13% and C1-26% and the fiveyear risk of a 30% decline in eGFR or progression to ESKD according to the IIgAN-PT was 10.5% (IQR 5.5;15.5). At baseline, eGFR was 129 ml/min/1.73m2 (IQR 109.8-150.3) and 20 (87%) patients had significant proteinuria. Over 3.1 (IQR 0.7;7.5) years of follow-up, the median annual eGFR decline was -1.9 (IQR -13.6;1.1) ml/min/1.73 m2 corresponding to -11.8% (IQR -19.1;0.61), and eGFR decreased ≥30% in 3 (13%) patients. Proteinuria remission occurred in 6 (27%) cases. The composite outcome was met by 15 (65%) patients (eGFR decreased in 14 (61%) and 1 (5%) patient received a kidney transplant). No significant correlations were found between MEST-C and IIgAN-PT scores at the time of biopsy and the occurrence of individual and composite renal outcomes over follow-up.
Conclusion: The sample size may have limited our ability to find significant correlations. Adapted tools may be needed to accurately predict renal outcomes in the pediatric population with IgAN after a period of observation post-biopsy.
Palavras Chave: IgA Nephropathy, MEST-C, paediatrics