Kidney transplantation outcomes in recipients with end-stage kidney disease due to primary vesicoureteral reflux: a case-control study.

purposeVesicoureteral reflux (VUR) may lead to reflux nephropathy and end-stage kidney disease (ESKD). Whether ESKD due to primary VUR identifies kidney transplant recipients at higher long-term graft risk remains incompletely defined, particularly when VUR phenotype, bladder status, reconstructive history, and infection burden are not captured.

methodsWe performed a retrospective 1:3 case-control study of kidney transplant recipients with ESKD attributed to primary VUR and non-VUR controls transplanted at a tertiary center. Patients whose primary ESKD etiology was bladder exstrophy, epispadias, posterior urethral valves, neurogenic bladder, prior cystectomy, complex congenital lower urinary tract anomalies, or myelomeningocele were not included in the primary VUR cohort. The dataset captured age at ESKD, VUR grade and laterality, dominant renal involvement, native ureteral reimplantation, native nephrectomy, clean intermittent catheterization, bladder augmentation, urinary reconstruction, and UTI episodes during the 12 months before and after transplantation. The primary endpoint was death-censored graft failure.

resultsThe cohort included 32 primary VUR recipients and 96 controls. Median age at ESKD among VUR recipients was 31 years (IQR 22.8-39.0), and median age at transplantation was 39 years (IQR 30-46). VUR grade was IV in 9/32 recipients (28.1%) and V in 23/32 recipients (71.9%); VUR was bilateral in 22/32 (68.8%). Native ureteral reimplantation/UCNA was recorded in 25/32 (78.1%), native nephrectomy in 13/32 (40.6%), clean intermittent catheterization in 12/32 (37.5%), and bladder augmentation in 6/32 (18.8%). UTI burden decreased from 48 episodes during the 12 months before transplantation to 15 episodes during the 12 months after transplantation; recurrent UTI decreased from 15/32 (46.9%) to 1/32 (3.1%). Post-transplant cystographic evaluation was not routine; graft VUR was documented in no patient. Graft failure occurred in 14/32 VUR recipients (43.8%) and 46/96 controls (47.9%). Estimated 10 year death-censored graft survival was 66.8% in the VUR group and 65.3% in controls (log-rank p = 0.977). VUR was not associated with graft failure in the crude Cox model (HR 1.01, 95% CI 0.55-1.84; p = 0.978) or in an exploratory adjusted model (HR 0.88, 95% CI 0.48-1.62; p = 0.677).

conclusionIn this single-center cohort, ESKD due to primary VUR was not associated with inferior death-censored kidney graft survival. These phenotype data indicate that the prognostic question in VUR is not the diagnostic label alone, but the combination of reflux severity, bladder/reconstructive status, native urinary tract management, and infection burden.