Effectiveness of a 5-Day External Stenting Protocol on Urological Complications After Renal Transplantation

Robert C. Minnee 0 1 2 Frederike J. Bemelman 0 1 2 Pilar P. Laguna Pes 0 1 2 Ineke J. M. ten Berge 0 1 2 Dink A. Legemate 0 1 2 Mirza M. Idu 0 1 2 0 F. J. Bemelman I. J. M. ten Berge Renal Transplant Unit, Department of Nephrology, Academic Medical Center , Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands 1 R. C. Minnee D. A. Legemate M. M. Idu (&) Department of Surgery, Academic Medical Center , Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands 2 P. P. Laguna Pes Department of Urology, Academic Medical Center , Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands Background Ureteral stents are successful in reducing urological complications after renal transplantation. However, the optimal duration and method of stenting have not yet been clarified. The objective of the present study was to investigate the frequency of urological complications when a 5-day external stented ureterocystostomy protocol was followed. Methods A single-center nonrandomized analysis of 392 kidney transplantations between June 2003 and June 2007 was conducted. From July 2005 all 196 renal transplant recipients received a 5-day external stented ureterocystostomy. A urological complication was defined as any cause leading to the placement of a percutaneous nephrostomy catheter and/or surgical revision of the ureterocystostomy. Results In the non-stented group, 21 of the 196 patients (10.7%) developed a urological complication compared to 13 patients (6.6%) in the stented group (p = 0.151). In the stented group, 2 of the 66 recipients of a living donor transplant (3.0%) developed a urological complication compared to 8 of the 59 recipients (13.6%) in the non-stented - group (P = 0.030). Eleven of 130 recipients of a deceased donor transplant (8.5%) in the stented group developed a urological complication, compared to 13 of the 137 recipients (9.5%) in the non-stented group (P = 0.769). The surgical revision rate of the stented and the non-stented group was 5/13 39% and 6/21 29%, respectively. Conclusions A 5-day routine external stent protocol is efficacious in living donor renal transplantation in preventing early postoperative ureter obstruction, but this stenting period seems inadequate for deceased donor renal transplantation. Urological complications remain an important source of morbidity and occasionally mortality, after renal transplantation. The two major urological complications after renal transplantation are urinary leakage and obstruction, mostly located at the ureterovesical junction or in the distal transplant ureter. Two meta-analyses have demonstrated that on comparison with a non-stented ureterocystostomy, a stented ureterocystostomy leads to a significantly lower urological complication rate (odds ratio 0.24, 95% confidence interval [CI] 0.070.77; P = 0.02) [1, 2]. This finding has been confirmed by two recent studies, one of which showed that stenting was more cost-effective. Accordingly, we changed our surgical technique from non-stented to stented ureterocystostomy [3, 4]. However, using a routine stenting protocol, the number needed to treat (NNT) to prevent one urological complication is high, ranging from 10 to 30 [2]. In addition, the optimal duration of stenting and method of stenting have yet to be determined. The aim of the present study was to analyze the results of a short (5-day) external stented ureterocystostomy protocol on the occurrence of urological complications. Patients and methods All 392 consecutive patients who underwent renal transplantation between June 2003 and June 2007 at the Academic Medical Center, Amsterdam, were included in the study. From July 2005 all 196 renal transplant recipients received a 5-day external stented ureterocystostomy. All procedures were single renal transplants performed through an extraperitoneal approach in the iliac fossa. The renal vein was anastomosed to the external iliac vein, and the renal artery was anastomosed to the external iliac artery. The method used to establish urinary continuity was either the extravesical ureterocystostomy (LichGregoir method) or the intravesical ureterocystostomy (PolitanoLeadbetter method), according to the personal preference of the surgeon. The ureteroneocystostomy was stented with an externally draining 8 French (Fr) catheter for 5 days. The stent was introduced into the bladder through a direct suprapubic bladder puncture and positioned in the transplant renal pelvis. The stent drained externally and was sutured to the bladder mucosa and to the skin. Postoperatively all patients had an indwelling bladder catheter. The operation day was counted as day 0. The stent was routinely removed on the fifth postoperative day. The bladder catheter was removed in all patients on day 7 after urinary leakage had been excluded by cystography on the same day. All patients were followed at our center for at least 1 year after successful transplantation. After 1 year, patients were transferred to their referral center. Standard immunosuppression consisted of prednisolone, a calcineurin inhibitor, mycophenolate mofetil, and prophylactic antiCD25 monoclonal antibody (basiliximab). Initial episodes of acute rejection were treated with pulse doses of methylprednisolone; second episodes, with thymoglobulin. Delayed graft function was defined as the need for dialysis within the first postoperative week. Renal transplant function was monitored by serial serum and urine creatinine, urinary output, and renography. Renal graft failure was defined as removal of the graft or loss of function requiring return to dialysis. After transplantation, the urinary output volumes through the stent and the indwelling bladder catheter were collected separately each day. These urinary output volumes were only measured in the stented group. A urological complication was defined as any cause (e.g., urinary fistula, leakage, ureteral obstruction) requiring a percutaneous nephrostomy catheter and/or surgical revision. Urinary tract infections and vesicoureteral reflux were not counted as urological complications. Urinary tract infection was defined as bacteriuria confirmed by a positive urine culture. If indicated, a percutaneous nephrostomy catheter was inserted and antegrade pyelography was performed. The nephrostomy catheter was left in place to maintain renal excretory function. Routinely, the nephrostomy catheter was changed every 6 weeks at our outpatient clinic. If the urinary obstruction persisted despite a well-functioning percutaneous nephrostomy catheter, an operative reconstruction was usually performed 36 months later. Statistical analysis Comparisons of categorical data were performed using the Chi-square test. Continuous data were compared between the groups using the MannWhitney U-test. Univariate logistic regression analysis was performed to identify risk factors for urological complication. The graft survival rates were calculated by the KaplanMeier technique and the log-rank test. A P value of \ (...truncated)