Transplant Ureteral Strictures Research Articles

Editorial Comment: Using a Reconstructive Ladder for Surgical Reconstruction of Transplant Ureteral Stricture Disease

Editorial Comment: Using a Reconstructive Ladder for Surgical Reconstruction of Transplant Ureteral Stricture Disease

Using a Reconstructive Ladder for Surgical Reconstruction of Transplant Ureteral Stricture Disease

Objective: Reconstruction of transplant ureteral stricture disease (USD) is a challenging surgical problem. In this article, we review our reconstructive ladder for robotic reconstruction of transplant USD and report our outcomes. Materials and Methods: We performed a retrospective review of patients undergoing robotic transplant reimplantation for USD after kidney transplantation at our institution between 11/2021 and 3/2023. Only patients with at least 1-year follow-up were included. The first rung of our reconstructive ladder is a side-to-side nontransecting reimplant. We prefer this method whenever possible because it avoids transection of the ureter, preserving the fragile blood supply. When this technique is not possible, because of long stricture length and/or limited bladder mobility, we proceed to the second rung of our reconstructive ladder, a Boari flap reconstruction. Surgical success in our cohort was defined as being hardware-free without evidence of ureteral obstruction on imaging. Results: There were 6 patients in our cohort: 3 underwent side-to-side reconstruction and 3 underwent Boari flap reconstruction. Median console time was 139 minutes (interquartile range [IQR] 85-175), estimated blood loss was 25 milliliters (IQR 25-81), and length of stay was 1 day (IQR 1-3). We had one major (Clavien ≥ III) complication, which was an intensive care unit transfer postoperatively for hypertension requiring a nicardipine drip. Median follow-up was 14 months (IQR 13-18) with a 100% surgical success rate. Conclusion: Utilization of a reconstructive ladder for management of transplant USD may allow for a systematic approach based on reconstructive principles. Our approach was associated with excellent intermediate-term outcomes.

Robotic-assisted Laparoscopic Repair of Kidney Transplant Ureteral Strictures

Background and ObjectiveTo evaluate outcomes of robotic assisted transplant ureteral repair (RATUR) for the management of kidney transplant ureteral strictures (TUS). MethodsWe retrospectively analyzed 41 consecutive patients who underwent RATUR for TUS at multiple tertiary referral centers between January 2016 and December 2022. RATUR was performed utilizing a robotic assisted transperitoneal approach. The primary outcome was stricture recurrence rate and secondary outcomes included postoperative complicate rate, determining factors impacting with allograft functional recovery, and rate of conversion to open surgery. Categorical and continuous variables are displayed as total number (Percentage) or median [Interquartile Range] respectively. Pearson correlation coefficient was utilized to assess categorical variable correlation with creatinine. ResultsThe median age was 56 years [44, 66]. The female to male ratio was 1.1:1. Approximately 66% of patients were dialysis dependent prior to kidney transplantation. TUS was identified at a median time of 4 months [2, 15.5] following kidney transplant. Median stricture length was 2 cm [1.22, 2.9cm]. There were no TUS recurrences with a median follow-up of 36 months [24, 48]. There were 3 Clavien Grade 2 and 1 Clavien grade 3 complications (9.5%). No baseline characteristics or preoperative diagnostics were correlated with a long-term decline in renal allograft function. ConclusionRATUR has excellent and durable outcomes with low complication rates. These findings encourage the use of a minimally invasive definitive repair as a first line treatment option for the management of TUS.

VE22 - Robot-assisted left ureteral reimplantation for treating transplant ureteral stricture: A modified V-Y technique with bladder flap

VE22 - Robot-assisted left ureteral reimplantation for treating transplant ureteral stricture: A modified V-Y technique with bladder flap

Clinical analysis of fifteen transplant ureteral stricture cases

This research aims to explore the clinical characteristics and treatment of transplant ureteral strictures. We retrospectively analyzed the clinical data from fifteen patients diagnosed with transplant ureteral stricture. Of the fifteen patients, five underwent regular ureteral stent or nephrostomy tube exchanges, while ten underwent open surgery. There were no significant differences in basic clinical characteristics between the two groups. The median follow-up time for regular ureteral stent or nephrostomy tube exchanges and open surgery group was 36.8 (11.8-56.0) months and 25.0 (4.5-31.2) months, respectively. Among patients who underwent regular exchanges, one required regular dialysis. Nine patients in the open surgery group had successful removal of the ureteral stent. Our findings suggest that regular ureteral stent or nephrostomy tube exchanges, as well as open surgery, are effective treatment options for transplant ureteral strictures.

Contemporary risk factors for ureteral stricture following renal transplantation.

Allograft ureteral strictures after renal transplantation impact graft function and increase patient morbidity. They can be challenging to treat and may require complex surgical repair. Therefore, the objective of this study was to identify contemporary risk factors for the development of post-renal transplant ureteral strictures. A retrospective analysis was performed on all renal transplant patients at Vancouver General Hospital from 2008-2019. Demographics, clinical parameters, and outcomes were compared between patients who did and did not develop ureteral strictures. Putative risk factors for ureteral stricture were analyzed using logistic regression. A total of 1167 patients were included with a mean followup of 61.9±40.8 months. Ureteral strictures occurred in 25 patients (2.1%). Stricture patients had no demographic differences compared to non-stricture patients but had significantly higher rates of postoperative complications, longer hospital stays, and decreased renal function one year post-transplant (all p<0.05). On multivariable analysis, cold ischemia time >435 minutes (odds ratio [OR] 43.9, confidence interval [CI] 1.6-1238.8, p=0.027), acute rejection (OR 3.0, CI 1.1-7.4, p=0.027), and postoperative complications (OR 112.4, CI 2.4-5332.6, p=0.016) were risk factors for stricture. Renal transplant patients with ureteral stricture experience greater morbidity and reduced post-transplant renal function compared to non-stricture patients. Our findings support attempts to reduce cold ischemia time, acute rejection, and postoperative complications to mitigate this potential complication. Our study is limited by the low incidence of ureteral stricture resulting in a small sample of stricture patients. Future research in a larger, multicenter setting is warranted.

The utility of native ureter in the management of ureteral complications in children after renal transplantation.

Ureteral complications after renal transplantation in children are a major source of morbidity. Management is complex and variable. With IRB approval, health records were retrospectively reviewed of patients who: were <18years, underwent kidney transplant between 1997 and 2017, had at least 2years of follow-up, and underwent interventions due to post-transplant ureteral complications. Of 136 patients, seventeen (13%) required ureteral intervention due to stricture (n=3), reflux (n=12), or both (n=2). Transplant occurred at median 10.5years (3.1-14.7). Reconstruction occurred at median 10months (7-15) after transplant. Pre-existing bladder pathology was present in 6 (35%) patients. Four of five patients with strictures had at least one endoscopic balloon dilation. Ultimate management included reimplantation, ureteroureterostomy of native to transplant ureter, pyeloureterostomy to native ureter, multiple endoscopic interventions followed by a Boari flap, or multiple failed endoscopic interventions. Fourteen patients with VUR underwent reimplantation (n=5), ureteroureterostomyof native to transplant ureter (n=4), pyeloureterostomyto native ureter (n=4), and one underwent endoscopic injection with Deflux of the transplant ureter. Only one patient had a non-functioning graft due to ureteral complication. All patients were alive at follow-up (median 17years [12-19]). Transplant ureteral reflux and stricture are significant complications following pediatric renal transplantation and may require surgical management. In our population, reflux or stricture requiring ureteral reconstruction occurred in 10% and 4%, respectively. Endoscopic interventions were rarely successful. Native ureters were used for ureteral reconstruction in more than two thirds of patients should be considered in management of ureteral complications.

Robot-assisted Transplant Ureteral Repair to Treat Transplant Ureteral Strictures in Patients after Robot-assisted Kidney Transplant: A Case Series

To describe the use of robotic-assisted transplant ureteral repair (RATUR) for treating transplant ureteral stricture (TUS) in 3 patients who had undergone robot assisted kidney transplant (RAKT). We reviewed the medical records of 3 patients who experienced TUS after RAKT and who underwent RATUR between 2017 and 2020. The patients' RAKT, post-transplant clinical course, endourological interventions, reoperation, and recovery were assessed. All patients diagnosed with TUS presented with deterioration of kidney function after RAKT. Method of diagnosis included ultrasound, antegrade ureterogram, and CT scan. All 3 patients had a short (<1 cm) area of TUS and underwent RATUR. For 2 patients, distal strictures were bypassed with modified Lich-Gregoir ureteroneocystostomy reimplantation. One patient was treated with pyelo-ureterostomy to the contralateral native ureter. No intraoperative complications, conversions to open surgery, or significant operative blood loss requiring blood transfusion for any patient were observed. Also, no patients had urine leaks in the immediate or late postoperative period. After RATUR, 2 patients developed Clavien grade II complications with rectus hematoma or urinary tract infection. RATUR is a technically feasible operation for kidney transplant patients with TUS after RAKT. This procedure may provide the same benefits of open operation without promoting certain comorbidities that may occur from open surgical procedures.

Robotic Surgery for the Reconstruction of Transplant Ureteral Strictures

ObjectiveTo demonstrate the feasibility and success of a robotic approach to reconstruction of ureterovesical anastomotic strictures in kidney transplants. Materials and MethodsBetween November 2017 and December 2019, a total of 5 patients with transplant ureteral stricture were identified and treated with robot assisted laparoscopic repair. All patients were confirmed to have ureteral stricture with a preoperative antegrade nephrostogram through their nephrostomy tube and cystogram. The patients demographics, ureteral characteristics, type of procedure, and outcomes are reported. ResultsAll patients were diagnosed after evaluation for renal deterioration. The average age of the patients was 49 years old. The average stricture length was 2.5 cm, and the location was variable, though more commonly in the distal ureter. Three patients required a pyelo-vesicostomy, while 2 required a ureteroneocystostomy. The mean length of stay was 2.2 days. Average follow-up was 97 days, with all 5 patients having successful outcomes, no strictures or delayed leaks were identified. There were no wound infections or readmissions within 30 days. ConclusionThough a complex repair, the robot-assisted approach to transplant ureter reconstruction using either an end to side neoureterocystotomy or direct pyelo-vesicotomy is technically feasible and successful. Given the many advantages inherent in comparison to an open approach, the robotic repair offers significant advantages to both the patient and the surgeon who is experienced with robotic surgery and reconstructive principles.

Comparison of tandem ureteral stents, cryoplasty, and cutting balloon ureteroplasty in treatment of refractory transplant ureteral strictures.

The objective of study was to compare clinical outcome of cryoplasty, tandem stents, and cutting balloon ureteroplasty as "bailout procedures" to prevent surgical intervention or stent dependency in renal transplant patients with refractory ureteral stricture. All patients who underwent a bailout procedure from June 11, 2003, to August 8, 2015, at a single institution were reviewed retrospectively. Refractory ureteral stricture was defined as ureteral stenosis not responding to at least two prior percutaneous plain balloon ureteroplasties. Primary patency was defined as stable allograft function following the procedure with unobstructed urine outflow, not requiring indwelling ureteral stent, repeat ureteroplasty, or surgical revision. Sixty-one procedures were performed on 51 patients. Patients were followed up for a median of 286days. Overall primary patency rate was 26.1%. Primary patency rate by method was 38.1%, 23.1%, and 14.3% after cryoplasty, tandem stent placement, and cutting balloon dilatation, respectively (P=.260). Primary patency rate was higher in early (<3months post-transplant) ureteral strictures (35.7% vs 13.3%; P=.047). More complications identified in patients who had tandem ureteral stents (P=.00754). As some renal transplant patients may not be good operative candidates for ureteral revision, it would be reasonable to attempt one of these "bailout" interventions as long as the clinical team and patient are aware of overall low potential for achieving primary patency.

3:54 PM Abstract No. 114 Percutaneous treatment of renal transplant ureteral strictures using multiple parallel ureteral stents

3:54 PM Abstract No. 114 Percutaneous treatment of renal transplant ureteral strictures using multiple parallel ureteral stents

V02-03 APPLICATION OF ROBOTIC ASSISTANCE TO TRANSPLANT URETERONEOCYSTOSTOMY

INTRODUCTION AND OBJECTIVES:Urologists are called upon to assist in management of ureteral strictures following renal transplantation. Refractory strictures can be managed with surgical reconstruction by performing ureteroneocystostomy or pyelovesicostomy. Transplant ureteroneocystostomy is often performed using an open approach. Challenges inherent to this surgery including periureteral fibrosis can be tackled with a robotic approach using advances in robotic surgical tools. Here we demonstrate our technique and rationale for performing robotic-assisted transplant ureteroneocystostomy in select patients.METHODS:We present a single surgeon's initial case series of three patients who underwent transplant ureteroneocystostomy using the daVinci® robotic surgical system, as well as discuss what influences determination of a patient's candidacy for this approach.RESULTS:Three patients with transplant ureteral strictures were identified. The median age was 61 years (26-62 years). All 3 patients failed attempts ...

Minimally-Invasive Ureteral Reconstruction for Ureteral Complications of Kidney Transplants

ObjectiveTo present the technique, feasibility and results of minimally-invasive reconstruction of the transplanted ureter using the native ipsilateral ureter in post-transplant ureteral strictures and vesicoureteral reflux (VUR) causing graft pyelonephritis. Ureteral complications after kidney transplantation represent a significant cause of morbidity potentially leading to graft dysfunction or loss. MethodsA prospective database from October 2011 to August 2018 identified renal transplant recipients who underwent minimally-invasive pyeloureterostomies or ureteroureterostomies using the ipsilateral ureter. Indications for either transplant ureteral stricture or VUR correction were assessed. Preoperative evaluation included a technetium-99m mercaptoacetyltriglycine renal scan to assess residual native renal function and either a video cysto-urethrogram or cystoscopy and retrograde pyelography. Postoperative patency was evaluated with either cystograms or antegrade nephrograms in conjunction with a technetium-99m mercaptoacetyltriglycine study. ResultsSeven patients were followed with a mean follow-up time of 20.9 months (range 4.7-64.8 months). Three cases of VUR causing graft pyelonephritis and 4 cases of transplant ureteral stricture were identified. Five minimally-invasive transplant-to-native pyeloureterostomies and 2 transplant-to-native ureteroureterostomies were performed. Six cases were performed robotically and 1 laparoscopically. No recurrent episodes of pyelonephritis were observed for patients treated for VUR causing graft pyelonephritis. Postoperative renal scans and contrast studies demonstrated no evidence of obstruction or urinary leaks in all cases. ConclusionMinimally-invasive reconstruction of the transplant ureter by pyeloureterostomy or ureteroureterostomy using the ipsilateral native ureter is feasible and can be safely performed with graft survival and acceptable complication rates.

Robot-assisted laparoscopic transplant-to-native ureteroureterostomy of an intraperitoneal renal allograft

The objective is to describe our experience with robot-assisted laparoscopic transplant-to-native ureteroureterostomy (UU) in a pediatric patient with an intraperitoneal renal allograft. We have previously demonstrated this technique for an extraperitoneal allograft. The patient is a 17-year-old female who had undergone a deceased donor renal transplant at 5 years of age. She developed acute kidney injury and hydronephrosis because of a ureteral stricture that developed after a right ovarian cyst excision. A retrograde pyelogram of her native ureter showed normal morphology. Her options were discussed and she proceeded with a robotic transplant-to-native UU. Robot-assisted laparoscopic transplant-to-native UU was performed via an intraperitoneal approach. The procedure time was 217min with an estimated blood loss of 10mL. Her postoperative course was unremarkable. After ureteral stent removal, her serum creatinine remained stable and follow-up imaging showed an improvement in hydronephrosis. Pediatric robot-assisted laparoscopic transplant-to-native UU for an intraperitoneal allograft is a technically feasible approach for the treatment of transplant ureteral strictures that combines the durability of open revision with the minimal invasiveness of endourologic management.

Outcomes of Kidney Transplant Recipients With Percutaneous Ureteral Interventions: A Single-Center Study.

BackgroundLong-term outcomes of kidney transplantation recipients with percutaneous ureteral management of transplant ureteral complications are not well characterized.MethodsElectronic records of 1753 recipients of kidney-alone transplant between January 2000 and December 2008 were reviewed. One hundred thirty-one patients were identified to have undergone percutaneous ureteral management, with placement of percutaneous nephrostomy tube or additional intervention (nephroureteral stenting and/or balloon dilation). Indications for intervention included transplant ureteral stricture or ureteral leak. Kaplan-Meier survival curves and multivariable regression modeling were performed to determine survival outcomes.ResultsKaplan- Meier graft survival (P = 0.04) was lower in patients with percutaneous ureteral intervention for transplant ureteral complication. Graft survival at 1, 5, and 10 years was 94.3% 78.3%, and 59.1% for no intervention and 97.2%, 72.1%, and 36.2% for intervention cohort. Patient survival (P = 0.69) was similar between cohorts. Multivariate analysis demonstrated no association with graft failure (hazard ratio, 1.21; 95% confidence interval, 0.67-2.19; P = 0.53) or patient death (hazard ratio, 0.56; 95% confidence interval, 0.22-1.41; P = 0.22) in intervention group. The major cause of graft failure was infection for percutaneous ureteral intervention group (20.4%) and chronic rejection for those without intervention (17.3%).ConclusionsKidney transplant recipients with percutaneous ureteral interventions for ureteral complications do not have a significant difference in graft and patient survival outcomes. Therefore, aggressive nonoperative management can be confidently pursued in the appropriate clinical setting.

A Rationale to Use Bladder Boari Flap Reconstruction for Late Kidney Transplant Ureteral Strictures

To evaluate the efficacy of Boari flap reconstruction (BFR) in the management of late-onset transplant ureteral strictures (TUS). Between March 2007 and March 2014, there were 730 patients who underwent kidney transplant (KTx) at our institution. We identified 16 patients with TUS, occurring more than 60 days after KTx. Baseline clinical and posttransplant characteristics were reviewed and stratified upon treatment modality. Outcomes for each treatment modality were determined. Median time from transplant to the treatment of TUS was 703 days (range, 65-2617 days). BFR was the most common treatment modality and was used in 87.5% of patients (n = 14/16). This procedure was performed as both a primary treatment and as a salvage procedure in recurrent TUS refractory to balloon dilation and neoureterocystotomy. Incidence of BFR failure was 6.3% (n = 1/14). BFR as a primary treatment was more successful compared to other methods (P < .01). Late TUS after KTx is a difficult complication to treat. Our study suggests that BFR can provide a higher success rate of primary treatment compared to other common treatment options. BFR can be used as a primary treatment of TUS or as a salvage procedure with similar success. Additional follow-up is necessary to evaluate the long-term efficacy of BFR for the treatment of late-onset TUS.

Robotic-assisted laparoscopic transplant-to-native ureteroureterostomy in a pediatric patient

ObjectiveManagement of late-occurring or long (>3 cm) post-transplant ureteral strictures usually requires open surgery, which includes ureteroureterostomy (UU) as an option. Recently, robotic-assisted laparoscopic UU for ectopic ureters in a duplicated system has been described. We report a case of a robotic-assisted laparoscopic transplant-to-native side-to-side UU in a 14-year-old girl with a stricture of nearly two-thirds of her transplant ureter 5 years after a cadaveric renal transplant. ResultsRobotic-assisted laparoscopic native-to-transplant UU was performed with resultant durable improvement in the patient's hydronephrosis and kidney function. ConclusionBased on our case and review of the literature, robotic-assisted laparoscopic UU should be part of the armamentarium for long or late-occurring transplant ureteral strictures.

Boari Flap Reconstruction Offers Superior Treatment for Late Transplant Ureter Strictures.

Appropriate management of late transplant ureteral strictures (TUS) after kidney transplant (KTx) is difficult. We evaluated risk factors, treatment and management outcomes of TUS over a 5-year period. 562 patients underwent KTx at our center from 3/07 to 3/12. We identified 15 (2.66%) patients with late (> 1 mo) TUS. Baseline clinical and post-transplant characteristics were reviewed. Time to development of TUS along with location and length of the stricture was identified. Treatment modalities and outcomes were reviewed. Baseline patient demographics and post-transplant characteristics are displayed on Tables I and II. Median follow-up period was 1071 days (range 361-2025 days). 5 TUS were considered short segment (≤2 cm) strictures. Median time from transplant to the treatment of TUS was 317 days (range, 37-1771 days). 4 patients (26.7%) underwent balloon dilation of TUS, but none had long-term success, all subsequently undergoing Boari flap reconstruction (BFR). Neoureterocystotomy was performed in 3/15 (20.0%) patients, with 1 failure requiring subsequent BFR. BFR was created in 13/15 (86.7%) patients. 1 BFR re-strictured and required revision surgery. BFR was associated with an increased success rate compared to other treatment methods (p<0.01). Late TUS is a difficult entity to treat. In our experience, endoscopic treatments were all unsuccessful and neoureterocystostomy may be unsuccessful due to difficulty in estimating the extent of scarred ureter. BFR can be used as a salvage procedure after more conservative efforts. BFR offers good surgical outcomes with long term follow up.Table: No Caption available.Table: No Caption available.

The accordion sign in the transplant ureter: ramifications during balloon dilation of strictures.

This study was designed to demonstrate the accordion sign within the transplant ureter and evaluate its ramifications during balloon dilation of strictures. A retrospective electronic chart and imaging review included demographic characteristics, procedure reports, and complications of 28 renal transplant patients having ureteral strictures treated with percutaneous balloon dilation reported in our transplant nephrology database during an 8-year period. The accordion sign was deemed present or absent on the basis of an imaging review and was defined as present when a tortuous ureter became kinked and irregular when foreshortened after placement of a wire or a catheter. Procedure-related urine leaks were categorized as occurring at the stricture if within 2 cm; otherwise, they were considered away from the stricture. The accordion sign was associated with a significantly greater occurrence of leaks away from the stricture (P = 0.001) but not at the stricture (P = 0.34). The accordion sign is an important consideration when performing balloon dilation procedures on transplant ureteral strictures, given the increased risk of leak away from the stricture. Its presence should prompt additional care during wire and catheter manipulations.

Primary Percutaneous Treatment of Transplant Ureteral Strictures Using Tandem Stents

To evaluate outcomes of primary (first-occurrence) treatment of renal transplant ureteral strictures using tandem parallel internal double-pigtail stents. A retrospective electronic chart review, including demographics, medical history, stricture intervention, and outcomes, was performed of patients with renal transplants with first-occurrence ureteral obstructions or leaks reported in a transplant nephrology database over a 4-year period, with a focus on patients treated primarily with tandem stents. Of 27 patients with first-occurrence ureteral obstruction or ureteral leak, 18 (67%) were treated primarily using tandem internal stents, with 15 (83%) of 18 stent-free for a minimum 90 days of follow-up. There was no significant difference between outcomes for male versus female patients (P>.99) or early versus late strictures (P = .53). Urinary tract infections (UTIs) occurred in 14 (78%) of 18 patients with tandem stents in place. Four patients were hospitalized<48 hours with UTI and sepsis; there were no other major complications. Patients with renal transplants can be successfully managed nonsurgically using tandem ureteral stents for the primary treatment of first-occurrence ureteral stricture. These patients may require more intensive monitoring for UTIs.