Kidney transplant recipients who experience acute kidney dysfunction without rejection (ADNR) have poor outcomes, François Paquot, MD, of the University of Liège Hospital in Belgium, and colleagues reported in BMC Nephrology.
Of 250 kidney transplant recipients (KTRs) at their institution, 93 had ADNR and 22 had acute rejection (AR; 14 cell- and 8 antibody-mediated) based on for-cause graft biopsies at a median 22 and 13 days after transplantation, respectively. The ADNR group included 53 recipients with strictly normal graft histology, 13 with borderline lesions, 15 with acute tubular necrosis, 8 with recurrent primary disease, and 4 with calcineurin inhibitor toxicity. The 135 control patients had stable kidney function without ADNR and AR within the first 2 years based on per-protocol biopsies. Delayed graft function did not differ among the groups.
At 12 months after transplantation, the estimated glomerular filtration rate (eGFR; based on the Modification of Diet in Renal Disease [MDRD] Study equation) was significantly higher in control vs ADNR vs AR patients: 57.6 vs 43.5 vs 46.5 mL/min/1.73m2, respectively. More importantly, nearly twice as many recipients with ADNR than controls had a 30% or more reduction in eGFR within 2 years: 29.9% vs 16.3%, respectively.
“ADNR occurs frequently and early post-KTx, and is associated with poor outcomes in KTR,” Dr Paquot and the team stated. “Prospective research needs to focus on the mechanisms of ADNR in order to improve the diagnostic and therapeutic management of KTR presenting with AKI.”
The pathophysiology of ADNR is probably multifactorial, they added. Imaging and other non-invasive approaches to graft biopsy are under development.
Paquot F, Weekers L, Bonvoisin C, et al. “Acute kidney dysfunction with no rejection” is associated with poor renal outcomes at 2 years post kidney transplantation. BMC Nephrol. doi:10.1186/s12882-019-1444-5