Is there long-term value of pathology scoring in immunoglobulin A nephropathy? A validation study of the Oxford Classification for IgA Nephropathy (VALIGA) update.

Abstract

BACKGROUND:

It is unknown whether renal pathology lesions in immunoglobulin A nephropathy (IgAN) correlate with renal outcomes over decades of follow-up.

METHODS:

In 1130 patients of the original Validation Study of the Oxford Classification for IgA Nephropathy (VALIGA) cohort, we studied the relationship between the MEST score (mesangial hypercellularity, M; endocapillary hypercellularity, E; segmental glomerulosclerosis, S; tubular atrophy/interstitial fibrosis, T), crescents (C) and other histological lesions with both a combined renal endpoint [50% estimated glomerular filtration rate (eGFR) loss or kidney failure] and the rate of eGFR decline over a follow-up period extending to 35 years [median 7 years (interquartile range 4.1-10.8)].

RESULTS:

In this extended analysis, M1, S1 and T1-T2 lesions as well as the whole MEST score were independently related with the combined endpoint (P < 0.01), and there was no effect modification by age for these associations, suggesting that they may be valid in children and in adults as well. Only T lesions were associated with the rate of eGFR loss in the whole cohort, whereas C showed this association only in patients not treated with immunosuppression. In separate prognostic analyses, the whole set of pathology lesions provided a gain in discrimination power over the clinical variables alone, which was similar at 5 years (+2.0%) and for the whole follow-up (+1.8%). A similar benefit was observed for risk reclassification analyses (+2.7% and +2.4%).

CONCLUSION:

Long-term follow-up analyses of the VALIGA cohort showed that the independent relationship between kidney biopsy findings and the risk of progression towards kidney failure in IgAN remains unchanged across all age groups and decades after the renal biopsy.

• Authors: Rosanna Coppo, Graziella D'Arrigo, Giovanni Tripepi, Maria Luisa Russo, Ian S D Roberts, Shubha Bellur, Daniel Cattran, Terence H Cook, John Feehally, Vladimir Tesar, Dita Maixnerova, Licia Peruzzi, Alessandro Amore, Sigrid Lundberg, Anna Maria Di Palma, Loreto Gesualdo, Francesco Emma, Cristiana Rollino, Manuel Praga, Luigi Biancone, Antonello Pani, Sandro Feriozzi, Rosaria Polci, Jonathan Barratt, Lucia Del Vecchio, Francesco Locatelli, Alessandro Pierucci, Yasar Caliskan, Agnieszka Perkowska-Ptasinska, Magdalena Durlik, Elisabetta Moggia, José C Ballarin, Jack F M Wetzels, Dimitris Goumenos, Marios Papasotiriou, Kresimir Galesic, Luka Toric, Aikaterini Papagianni, Maria Stangou, Luisa Benozzi, Stefano Cusinato, Ulla Berg, Rezan Topaloglu, Milena Maggio, Mai Ots-Rosenberg, Marco D'Amico, Colin Geddes, Olga Balafa, Marco Quaglia, Raffaella Cravero, Calogero Lino Cirami, Bengt Fellstrom, Jürgen Floege, Jesus Egido, Francesca Mallamaci, Carmine Zoccali, ERA-EDTA Immunonephrology Working Group
• Journal: Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (Nephrol Dial Transplant) Vol. 35 Issue 6 Pg. 1002-1009 (06 01 2020) ISSN: 1460-2385 [Electronic] England
• PMID: 30418652 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Validation Study)
• Copyright: © The Author(s) 2018. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Topics

• Adolescent
• Adult
• Child
• Cohort Studies
• Disease Progression
• Female
• Follow-Up Studies
• Glomerular Filtration Rate
• Glomerulonephritis, IGA (classification, pathology)
• Humans
• Kidney (physiopathology)
• Male
• Prognosis