Is delayed graft function associated with ureteral stenosis in the kidney transplant recipient? A case-control study

Ureteroureterostomy With Near-Infrared Ray Catheter in a Kidney Transplant

Transplant ureteral stenosis (US) is a complication of kidney transplantation (KT) that sometimes adversely affects kidney function. Endoscopic treatment may be selected as the initial treatment; however, the recurrence rate is high. Ureteral reconstruction is necessary as a secondary treatment, but it is often difficult to identify the transplanted ureter due to reoperation; therefore, transplanted ureter and renal arteriovenous injury are intraoperative complications that should be noted. The Near-Infrared Ray Catheter (NIRC™) fluorescent ureteral catheter (NIRFUC) fluoresces by illuminating near-infrared rays, facilitating the identification of intraoperative ureteral locations. Herein, we report the case of a 34-year-old woman who developed US following KT. She underwent balloon dilation for transplant US, but the stenosis recurred; therefore, she underwent transplant ureteral auto-ureteral anastomosis. Although it was difficult to identify and detach the transplanted ureter owing to adhesions, the use of NIRFUC facilitated the identification of the ureter in the surgical field and enabled safe end-side anastomosis between the transplanted ureter and the autologous ureter. In conclusion, although there is no consensus on the best method for complex transplantation-related US cases, NIRFUC may be used to safely identify and perform surgeries on the ureter.

Urological Complications in Kidney Transplant Recipients: Analysis of the Risk Factors and Impact on Transplant Outcomes in the Era of “Extended Criteria Donors”

Urological complications (UC) following kidney transplantation (KT) are associated with increased morbidity. The aim of this study is to evaluate the risk factors for UC in the era of “extended criteria donors” (ECD) and their impact on patient and graft survivals. A retrospective monocentric study of all patients undergoing KT from 2010 to 2019 with a follow-up ≥30 days was performed. Out of 459 patients (males: 296 (64.5%); age: 57 (19–77) years) enrolled, 228 (49.7%) received ECD organs, moreover, 166 (67.2%) grafts had a cold ischemia time ≥10 h. UCs were reported in 32 (7%) patients. In 21 (65.6%) cases UC occurred within 3 months post-KT and 24 (5.2%) were associated with early urinary tract infection (UTI). The overall 5 year patient and graft survival rates were 96.5% and 90.6%, respectively. UC decreased graft survival (UC-group: 75.0% vs. noUC-group: 91.8%, p < 0.001), especially if associated with early UTI (UC-group: 71.4% vs. noUC-group: 77.8%, p < 0.001). At multivariate analysis, early UTI after KT (OR: 9.975, 95%-IC: 2.934–33.909, p < 0.001) and delayed graft function (DGF) (OR: 3.844, 95%-IC: 1.328–11.131, p: 0.013) were significant risk factors for UC, while ECD graft did not increase the risk of post-transplant UC. ECD grafts are not associated with UC. DGF and early UTI post-KT increase the risks of UC and reduce graft survival in the long-term. Therefore, aggressive management of early post-transplant UTI and strategies to reduce DGF incidence, such as machine preservation, are essential to prevent UC after KT.

Development of Ureteral Stenosis/Obstruction in Kidney Transplant

This retrospective study describes the incidence and prevalence of ureteral stenosis/obstruction (US/O) in a cohort of 334 renal transplants recipients in our center over the last 5 years and evaluates the risk factors that may influence the occurrence of US/O. The parameters studied included the following: history of prostate disease, smoking, urinary tract infection, renal lithiasis, ureterovesical reflux, presence and level of polar artery, type of ureterovesical anastomosis, delayed graft function, double J catheter, lymphocele, urinoma, acute rejection, prolonged catheterization, post-transplant infravesical obstruction and BK virus infection, age of the donor and recipient, and months on dialysis. Also evaluated were the nadir creatinine and instances of cold ischemia, asystole, reanastomosis, and double J catheter removal. The average incidence of US/O was 7.6% and was significantly correlated with factors of alteration of the uretero-bladder dynamics without finding a relation to vascular factors.