Background Congenital defunctionalized bladders have abnormal storage dynamics such as low capacity and compliance. This presents a technical challenge for children undergoing kidney transplantation. Abnormal bladder dynamics may expose the allograft to increased hydrostatic pressures, resulting in dysfunction and failure. Creation of an end cutaneous transplant ureterostomy (TU) permits allograft drainage and avoids ureteral reimplantation into the extremely small bladder. In this study, we aim to describe our experience with series of TU while comparing outcomes/complications to a series of native ureterostomies (NU)
Methods We performed retrospective cohort review of all patients who underwent creation of cutaneous ureterostomies (both TU & NU) at our institution from 2014 to 2024. Data collected includes demographics, indication for ureterostomy, surgical techniques, short- and long-term complications, and post-operative management. Statistical comparison between continuous and categorical variables were calculated using Mann-Whitney U test and Fisher's exact test, respectively. Statistical significance was defined as an alpha value of less than 0.05.
Results A total of 32 patients had 38 ureterostomies created. Of those eight were TU,6 were bilateral NU, and 24 were unilateral NU. Of the 30 NU, 10 were loop and 20 were end ureterostomies. All TU were brought to the left side of the abdomen with right sided allografts, to preserve ureteral length for future undiversion as end ureterostomies. There were seven TU that were intentionally intraperitonealized after extraperitonealization of the original TU of the series led to obstruction All but one ureterostomy were immediately stented following the procedure for a mean duration of 12 days (range 5-53 days). Patients with NU were significantly younger that those with TU [median age (IQR) 3.3 mo (0.46-6.4) vs. 31.6 mo (26.9-35.1), p <0.01]. The most common post operative complication was a UTI, occurring in 62.5% of the overall cohort (75% TU vs. 58.3% NU (p=0.676)). Various degrees of hydronephrosis were still present in 21 (65.6%) patients (3 NU: 18 TU) on a 30-day-post operative ultrasound. Worsening hydronephrosis was present in four patients. 10/30 NU (33.3%) were placed on clean intermittent catheterization (CIC) at a median of 11.5 days post operatively compared to 7/8
(87.5%) TU at a median of 45.5 days post operatively (p=0.013). Indications for and frequency of CIC of the ureterostomies varied according to surgeon preference, worsening hydronephrosis, and/or worsening kidney function. Two patients after NU and 1 patient after TU underwent surgical revision for ureteral stricture (n=2) and stomal stenosis (n=1). No allograft was lost during the follow-up period [median 27.65 months (range 3.67-37.03)].
Conclusion TU is a safe and effective alternative to transplant ureteral implantation in select patients with congenital defunctionalized bladders that have extremely small bladder capacity. There was no difference in the incidence of post-operative UTIs between the NU and TU groups. There were higher rates of CIC of TU compared to NU, the cause of which remains unclear. Upfront CIC can be considered for all TU to help minimize urinary stasis and/or UTI.