AUTHOR=Tarragoni Rita , Congiu Giovanni , Mella Alberto , Augelli Giovanni , Fop Fabrizio , Dolla Caterina , Gallo Ester , Di Vico Maria Cristina , Faletti Riccardo , Bosio Andrea , Gontero Paolo , Costa Cristina , Cavallo Rossana , Mariano Filippo , Corcione Silvia , De Rosa Francesco Giuseppe , Fonio Paolo , Biancone Luigi TITLE=Different profiles of acute graft pyelonephritis among kidney recipients from standard or elderly donors JOURNAL=Frontiers in Medicine VOLUME=11 YEAR=2024 URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2024.1342992 DOI=10.3389/fmed.2024.1342992 ISSN=2296-858X ABSTRACT=Background

Acute graft pyelonephritis (AGPN) is a relatively common complication in kidney transplants (KTs); however, the effects on allograft function, diagnostic criteria, and risk factors are not well established.

Methods

Retrospective analysis of all consecutive adult KTs was performed between 01 January 2011 and 31 December 2018 (follow-up ended on 31 December 2019) to examine the association between the diagnosis of AGPN (confirmed with magnetic resonance imaging [MRI]) during the first post-transplantation year and graft outcomes.

Results

Among the 939 consecutive KTs (≈50% with donors ≥60 years), we identified 130 MRI-confirmed AGPN episodes, with a documented association with recurrent and multidrug-resistant bacterial urinary tract infections (UTIs) (p < 0.005). Ureteral stenosis was the only risk factor associated with AGPN (OR 2.9 [95% CI, 1.6 to 5.2]). KTs with AGPN had a decreased allograft function at the first year (ΔeGFR 6 mL/min/1.73 m2 [−2–15] in non-AGPN vs. −0.2 [−6.5–8.5] in AGPN, p < 0.001), with similar and negative profiles in KTs from standard or elderly donors. However, only KTs with AGPN and a donor <60 years showed reduced death-censored graft survival (p = 0.015); most of this subgroup received anti-thymocyte globulin (ATG) induction (40.4% vs. 17.7%), and their MRI presented either a multifocal AGPN pattern (73.9% vs. 56.7%) or abscedation (28.3% vs. 11.7%). No difference was noted in death-censored graft survival between early (<3 months post-KT) or late (3–12 months) AGPN, solitary/recurrent forms, or types of multidrug-resistant pathogens. Linear regression confirmed the independent role of multifocal pattern, abscedation, ATG induction, and donor age on the eGFR at the first year.

Conclusion

AGPN, influenced by multifocal presentation, ATG induction, donor age, and abscedation, affects kidney function and significantly impacts allograft survival in KTs with donors <60 years.