The Importance of Video Urodynamics in Selected Oligo-Anuric Patients Awaiting Renal Transplantation

Lower urinary tract (LUT) dysfunction can compromise renal graft function through high detrusor pressures, vesicoureteral reflux (VUR), and recurrent urinary tract infections (rUTIs). Patients with chronic oligo-anuria may have masked LUT symptoms (LUTS) due to reduced urine production. This study aimed to determine the prevalence and characteristics of LUT dysfunction identified using video-urodynamics (VUDS) in selected oligo-anuric patients undergoing renal transplant evaluation or post-transplant assessment.

We performed a single-centre retrospective analysis of patients undergoing VUDS between November 2020 and September 2025. Patients were included if oligo-anuric while awaiting renal transplantation with clinical history suggesting LUT dysfunction, or if oligo-anuric at the time of transplantation and subsequently developed rUTIs, declining graft function, or new LUTS. VUDS was performed according to International Continence Society standards with fluoroscopic assessment to assess VUR and site of BOO.

Thirty-nine patients (26 male, 13 female; median age 46 years) were included. VUR was demonstrated in 30/39 patients (77%), with 20 involving the transplant kidney. High-grade reflux (grade III-V) was present in 18 patients (46% of the cohort) (15 in transplant kidneys). In 24/30 patients with VUR (80%), reflux was associated with underlying bladder pathology that increased detrusor pressure. Pseudo-post-void residual due to reflux was observed in 18 patients.

LUT dysfunction is highly prevalent in selected oligo-anuric patients undergoing renal transplant evaluation. VUDS enables identification of high-pressure bladder pathology and VUR that may threaten graft integrity.