Robotic-assisted Laparoscopic Repair of Kidney Transplant Ureteral Strictures

OBJECTIVE

To evaluate outcomes of robotic-assisted transplant ureteral repair (RATUR) for the management of kidney transplant ureteral strictures (TUS).

METHODS

We 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.

RESULTS

The median age was 56years [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 4months [2, 15.5] following kidney transplant. Median stricture length was 2 cm [1.22, 2.9 cm]. There were no TUS recurrences with a median follow-up of 36months [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.

CONCLUSION

RATUR 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.

Effect of ureteral stricture in transplant kidney and choice of treatment on long-term graft survival

BACKGROUND

To explore the risk factors of ureteral stricture in transplant kidney and the clinical effects of different treatment methods.

METHODS

The 62 patients with transplant kidney ureteral stenosis as the experimental group, and another group of recipients from the same donor as the control group (n = 59 cases). The risk factors for ureteral stricture and the survival rate of transplant kidney were analyzed and compared. The 62 patients were divided into open operation, luminal operation, and magnetic compression anastomosis (MCA) operation group. The effect of the operation and the survival rate of transplant kidney among the three groups were compared.

RESULTS

In our study, we found that the above differences were statistically significant in clinical data such as gender, multiple donor renal arteries, history of infection, and delayed graft function (DGF) between the two groups (P < 0.05). Urinary tract infection and DGF history were the independent risk factors for the development of ureteral stricture. The open operation had the best treatment effect and the survival rate of the transplant kidney, followed by the MCA, the stricture recurrence rate in the luminal operation was the highest.

CONCLUSION

The ureteral stricture has a negative correlation with the long-term survival rate of the transplant kidney, the curative rate and long-term effect of open surgery are the best, stricture recurrence rate of luminal surgery is high, and it may require multiple operations in the future, the MCA is a new breakthrough and innovation in the treatment of ureteral stricture.

Robotic ureter reconstruction using the native ureter to treat long-segment ureteral stricture of the transplant kidney utilizing Indocyanine green: The first Korean experience

PURPOSE

Ureteral strictures are a common complication after kidney transplantation. Open reconstruction is preferred for long-segment ureteral strictures that cannot be resolved endoscopically; however, it is known to have the potential to fail. We report 2 successful cases of robotic reconstruction surgery of a transplant ureter using the native ureter with the aid of intraoperative Indocyanine green (ICG).

MATERIALS AND METHODS

Patients were placed in semi-lateral position. Using Da Vinci Xi, the transplant ureter was dissected, and the stricture site was identified. End-to-side anastomosis of the native ureter to the transplant ureter was performed. ICG was utilized to identify the course of the transplant ureter and confirm the vascularity of the native ureter.

RESULTS

Case 1: A 55-year-old female underwent renal transplantation at another hospital. She had recurrent febrile urinary tract infections (UTIs) and a ureteral stricture requiring percutaneous nephrostomy (PCN). The PCN and ureteral stent were removed successfully after surgery. The patient had only 1 febrile UTI episode after surgery. Case 2: A 56-year-old female underwent renal transplantation at another hospital. She had acute pyelonephritis 1-month post-transplantation, and a long-segment ureteral stricture was identified. She developed a UTI with anastomosis site leakage in the early postoperative period, which resolved with conservative treatment. The PCN and ureteral stent were removed 6 weeks after surgery.

CONCLUSIONS

Robotic surgery for managing long-segment ureteral stricture after kidney transplantation is safe and feasible. The use of ICG during surgery to identify the ureter course and its viability can improve the success.

Transplant Ureteral Stenosis after Renal Transplantation: Risk Factor Analysis

INTRODUCTION

The results of kidney transplants have improved dramatically in recent years, leading to reduced morbidity and mortality. Despite continuous improvements, urological complications occur at a rate of 2.6%-15%. Ureteral stenosis of graft ureters is the most common complication, with a probability of 0.5%-6.3%. This study aimed to determine the incidence of ureteral stenosis after kidney transplantation and identify risk factors that distinguish transplant patients with and without ureteral stenosis.

METHODS

This study retrospectively analyzed patients who had undergone kidney transplantation at the Department of Urology of the Friedrich-Alexander University Erlangen-Nuremberg between 2001 and 2015. Forty-seven patients developed ureteral stenosis during the operation. Most of the ureteral stenosis cases occurred in the first 4 months after transplantation. Kaplan-Meier analysis and the log-rank test were used to calculate the cumulative risk, and the Mann-Whitney U test was used nonparametrically. The significance level was set at p < 0.05.

RESULTS

Statistical analysis showed that residual diuresis (p = 0.008), cold ischemia time (CIT) (p = 0.040), the body mass index (p = 0.027), and donor serum creatinine value (p = 0.039) showed a significantly different distribution between recipients with or without ureteral stenosis after kidney transplantation. In multivariate Cox's regression modeling, residual diuresis and the donor serum creatinine level were identified as the only independent predictors of patients' stenosis-free survival.

CONCLUSION

Urological complications not diagnosed and treated in time endanger the success of kidney transplantation. After evaluating the kidney transplantation data of the patients at the Transplant Center Erlangen-Nuremberg from 2001 to 2015, residual diuresis, CIT, the body mass index, and donor serum creatinine value were found to influence the development of ureteral stenosis.

Simultaneous antegrade urography of the upper urinary tract and retrograde cystography combined with computed tomography imaging in the management of ureteral complications after renal transplantation

Background

To investigate the significance of simultaneous urography of the upper and lower urinary tract of transplanted kidneys combined with computed tomography urography (CTU), computed tomography arteriography (CTA), and computed tomography venography imaging in the planning of open surgery performed to treat any ureteral complications of a transplanted kidney.

Methods

In all, 24 patients with ureteral complications after renal transplantation were admitted, 12 of whom had renal graft ostomy during open surgery. Simultaneous antegrade urography of the upper urinary tract and retrograde cystography of the transplanted kidneys were performed on the patients. With the use of computed tomography imaging results, surgical planning was carried out.

Results

All surgeries were successfully completed according to preoperative planning. Three patients underwent end-to-end anastomosis of the ureter and bladder muscle flap, 8 patients underwent ureterocystostomy, and 1 patient underwent an end-to-end ureteral anastomosis. After the follow-up up to now, all the patients had stable renal function, and no complications such as ureteral stenosis or urine leakage have thus far reoccurred in the transplanted kidneys.

Conclusions

When open surgery is required to treat any ureteral complications following renal transplantation, preoperative multiangle imaging can be used to better understand the condition of the transplanted urinary tract and thus aid considerably in surgical planning.

Ureteral reimplantation after deflux failure for vesicoureteral reflux in renal transplant

PURPOSE

To evaluate the outcomes of ureteral reimplantation (UR) after failure of endoscopic treatment for symptomatic vesicoureteral reflux (VUR) in renal transplant recipients.

METHODS

We conducted a monocentric retrospective study that included all renal transplant recipients with failure of Deflux™ as first-line treatment of VUR from January 2007 to December 2020. Failure of Deflux™ was defined by: VUR on retrograde cystography and at least one acute pyelonephritis of the renal graft. The preferred surgical treatment was native ureteropyelostomy (NPUS) in the recent years. If the native ureter could not be used, ureteroneocystostomy (UNC) was performed. The primary outcome was the clinical efficacy of UR defined as the absence of acute graft pyelonephritis during follow-up.

RESULTS

Out of 1565 kidney transplantations, 119 (7.6%) had symptomatic VUR treated with bulking agent. 35 (29.4%) had Deflux™ failure and were addressed to UR: 21/35 (60%) NPUS and 14/35 (40%) UNC. The median estimated blood loss, operative time, and length of stay were 120 mL, 90 min, and 7 days, respectively. After a median follow-up of 7.1 (IQR 4.1-9.8) years, UR was clinically successful in a total of 32 patients (91.4%): 20 (95.2%) and 12 (85.7%) patients in the NPUS and UNC groups, respectively (p = 0.55). Three (8.5%) high-grade complications have been reported. No nephrectomy of native kidney was required in the NPUS group.

CONCLUSIONS

After failure of Deflux™ for VUR of renal graft, surgical treatment with native ureteropyelostomy or ureteroneocystostomy is associated to a high success rate and few high-grade complications.

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.

Robotic Surgery for the Reconstruction of Transplant Ureteral Strictures

OBJECTIVE

To demonstrate the feasibility and success of a robotic approach to reconstruction of ureterovesical anastomotic strictures in kidney transplants.

MATERIALS AND METHODS

Between 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.

RESULTS

All 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.

CONCLUSION

Though 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.

[Results of surgical revisions for ureteral complications after renal transplantation]

OBJECTIVE

To analyze the results of surgical revision for ureteral complication (ureteric stenosis or urinary leakage) after renal transplantation over a period of 10 years.

MATERIALS AND METHODS

We performed a retrospective study on 1313 consecutive kidney transplantations carried out in a University Hospital Center between 2005 and 2014. The data of the patients who developed a ureteral stenosis or a urinary leakage secondary to a renal transplantation were analyzed. Combined organ transplantations (kidney-liver and kidney-pancreas), as well as pediatric transplantations were excluded.

RESULTS

Seventy-six patients (5.8%) had ureteric stenosis or urinary leakage after renal transplantation. Forty-six patients (3.5%) underwent surgical revision: 27 for ureteral stenosis, 19 for urinary leakage. Early success was achieved in 26 patients (56.5%), including 14 ureteric stenosis (51.9%) and 12 urinary leakage (63.2%) (P=0.45). After a complementary endoscopic or surgical treatment, the final success rate was increased to 73.1% (34 patients): 20 ureteric stenosis (74.1%) and 14 urinary leakage (73.7%) (P=0.98). There were 2 graft losses (4.3%) and one death (2.2%). The mean glomerular filtration rate estimated by the MDRD was 44.58mL/min/1.73m² (±14.7) before surgery and 45.37mL/min/1.73m² (±16.5) 6 months after surgery (P=0.92).

CONCLUSION

Although frequently challenging, surgical revisions for ureteral complications after renal transplantation give good results, with a low rate of graft loss and mortality.

LEVEL OF EVIDENCE

4.

Impact of ureteral stricture and treatment choice on long-term graft survival in kidney transplantation

We aimed to evaluate the influence of urological complications occurring within the first year after kidney transplantation on long-term patient and graft outcomes, and sought to examine the impact of the management approach of ureteral strictures on long-term graft function. We collected data on urological complications occurring within the first year posttransplant. Graft survivals, patient survival, and rejection rates were compared between recipients with and without urological complications. Male gender of the recipient, delayed graft function, and donor age were found to be significant risk factors for urological complications after kidney transplantation (P < .05). Death censored graft survival analysis showed that only ureteral strictures had a negative impact on long-term graft survival (P = .0009) compared to other complications. Death censored graft survival was significantly shorter in kidney recipients managed initially with minimally invasive approach when compared to the recipients with no stricture (P = .001). However, graft survival was not statistically different in patients managed initially with open surgery (P = .47). Ureteral strictures following kidney transplantation appear to be strongly negatively correlated with long-term graft survival. Our analysis suggests that kidney recipients with ureteral stricture should be managed initially with open surgery, with better long-term graft survival.

How to stent the ureter after kidney transplantation in children?-A comparison of two methods of urinary drainage

Ureteral stenting after pediatric renal transplantation serves to prevent obstruction and urinary leakage, but can also cause complications. This study compares the complication rates of both methods. Data were retrospectively collected at Erasmus MC, Rotterdam, the Netherlands (splint group, n = 61) and Hospital for Sick Children, Toronto, Canada (JJ catheter group, n = 50). Outcome measures included urological interventions and incidence of UTIs during the first 3 months post-transplantation. The splint was removed after a median of 9 (IQR 8-12), the JJ catheter after 42 (IQR 36-50) days. Seven (11.5%) children in the splint group needed at least one urological re-intervention versus two in the JJ catheter group (P-value .20). UTIs developed in 19 children (31.1%) in the splint group and in twenty-five (50.0%) children in the JJ catheter group (P-value .04), with a total number of 27 vs. 57 UTIs (P-value .02). Nine (33.3%) vs. 35 (61.4%) of these, respectively, occurred during the presence of the splint (P-value <.001). Children with a JJ catheter developed more UTIs than children with a splint; the latter, however, tended to require more re-interventions. Modification of either method is needed to find the best way to stent the ureter.

Urologic Complications After Renal Transplant: A Single-Center Experience

OBJECTIVES

Urologic complications after kidney transplant are associated with significant morbidity, mortality, and prolonged hospital stay. An intervention or second surgical procedure is frequently required. Here, we report urologic complications in adult kidney recipients.

MATERIALS AND METHODS

Since 2006, 171 adult kidney transplant procedures have been performed at the Gazi University Transplantation Center (Ankara, Turkey). Among these patients, there were 65 adult female (38%) and 106 adult male (62%) recipients. Donor source included 61 deceased donations (36%) and 110 living related donations (64%). The Haberal corner-saving technique was used for ureteroneocystostomy anastomosis. All recipients received a calcineurin-based triple immunosuppression regimen. All recipients also received trimethoprim/sulfamethoxazole prophylaxis for 3 months after transplant.

RESULTS

In the 171 adult kidney recipients analyzed for urologic complications, mean age was 32.5 ± 14.1 years (median: 32.5 y; range, 18-67 y); mean donor age was 41 ± 14.2 years (median: 42 y). We focused on 3 specific urologic complications: urine leak, ureteric stenosis, and symptomatic vesicoureteral reflux. In our study group, urologic complications were encountered in 7 patients (4%), with 5 complications detected in the early period and 2 complications detected in the late period. No symptomatic vesicoureteral reflux complications were shown in this study group. Urologic complications did not result in any patient deaths or graft loss.

CONCLUSIONS

In this study, the Haberal corner-saving suture technique with double J stent seemed to have a protective effect for development of urologic complications.

[Management of urological complications after renal transplantation]

Urological complications after kidney transplantation can cause a major reduction in renal function. Surgical complications like urinary leakage and ureteral obstruction need to be solved by a specialist in the field of endourological procedures and open surgical interventions. The article summarizes this and other common urological problems after kidney transplantation.

Independent risk factors for early urologic complications after kidney transplantation

Urologic complications are the most frequent technical adverse events following kidney transplantation (KTX). We evaluated traditional and novel potential risk factors for urologic complications following KTX. Consecutive KTX recipients between December 1, 2006 and December 31, 2010 with at least six-month follow-up (n = 635) were evaluated for overall urologic complications accounting for donor, recipient, and transplant characteristics using univariate and multivariate logistic regression. Urologic complications occurred in 29 cases (4.6%) at a median of 40 d (range 1-999) post-transplantation and included 17 ureteral strictures (2.6%), five (0.8%) ureteral obstructions due to donor-derived stones or intraluminal thrombus, and seven urine leaks (1.1%). All except two complications occurred within the first year of transplantation. Risk factors for urologic complications on univariate analysis were dual KTX (p = 0.04) and renal artery multiplicity (p = 0.02). On multivariate analysis, only renal artery multiplicity remained significant (aHR 2.4, 95% confidence interval 1.1, 5.1, p = 0.02). Donation after cardiac death, non-mandatory national share kidneys, donor peak serum creatinine > 1.5 mg/dL or creatinine phosphokinase > 1000 IU/L, and donor down time were not associated with urologic complications. Our data suggest that donor artery multiplicity is an independent risk factor for urologic complications following KTX.

Management of urologic complications in renal transplantation: a single-center experience

INTRODUCTION

Ureterovesical complications subsequent to renal transplantation are associated with a high morbidity leading to graft loss or even death. In the present study, the management of these complications by using interventional and surgical procedures (native pyeloureterostomy [NPUS]/ureteroureterostomy [NUU] vs ureteroneocystostomy [UNC]) was evaluated retrospectively.

PATIENTS AND METHODS

Between 1994 and 2012, a total of 780 kidney transplantations (690 deceased and 90 living donors) were performed at our institution. Demographic, clinical, and laboratory data from patients with urologic complications were analyzed and compared.

RESULTS

Fifty patients (6.4%) exhibited ureterovesical complications, and 18 patients (36%) were operated on immediately. In 32 (64%) of 50 patients, an interventional procedure was initially performed, with 21 patients (66%) undergoing operation due to therapy failure. NPUS/NUU and UNC were performed in 26 (66.6%) and 13 (33.3%) patients, respectively. Indications for an operation were ureteral stenosis in 12 patients (30.8%), ureteral necrosis and urine leakage in 19 patients (48.7%), and symptomatic vesicoureteral reflux in 8 patients (20.5%). Long-term results were comparable between all groups.

CONCLUSIONS

Surgical revision of ureteral complications should be the standard therapy. NPUS/NUU, UNC, and the successful interventional procedures did not differ significantly in terms of long-term results.

Outcomes of Percutaneous Management of Anastomotic Ureteral Strictures in Renal Transplantation: Chronic Nephroureteral Stent Placement with and without Balloon Dilatation

PURPOSE

This study was designed o evaluate outcomes of percutaneous management of anastomotic ureteral strictures in renal transplants using nephroureteral stents with or without balloon dilatation.

METHODS

A retrospective audit of 1,029 consecutive renal transplants was performed. Anastomotic ureteral strictures were divided into two groups: nephroureteral stent only (NUS) and NUS+PTA (nephroureteral stent plus percutaneous transluminal angioplasty), with each cohort subdivided into early versus late presentation (obstructive uropathy occurring <90 day or >90 days from transplant, respectively). Overall and 6-month technical success were defined as removal of NUS any time with <30 % residual stenosis (any time lapse less or more than 6 months) and at >6 months, respectively. Patency was evaluated from NUS removal to last follow-up for both groups and compared.

RESULTS

Sixty-seven transplant patients with 70 ureteric anastomotic strictures (6.8 %, n = 70/1,029) underwent 72 percutaneous treatments. 34 % were late (>90 days, n = 24/70), and 66 % were early (<90 days, n = 46/70). Overall technical success was 82 % (n = 59/72) and 6-month success was 58 % (n = 42/72). Major and minor complications were 2.8 % (n = 2/72), and 12.5 % (n = 9/72). NUS+PTA did not improve graft survival (p = 0.354) or patency (p = 0.9) compared with NUS alone. There was no difference in graft survival between treated and nontreated groups (p = 0.74).

CONCLUSIONS

There is no advantage to PTA in addition to placement of NUS, although PTA did not negatively impact graft survival or long-term patency and both interventions were safe and effective. Neither the late or early groups benefited from PTA in addition to NUS. Earlier obstructions showed greater improvement in serum creatinine than later obstructions.

Independent risk factors for urological complications after deceased donor kidney transplantation

Urological complications after kidney transplantation are mostly related to the ureteroneocystostomy, often requiring interventions with additional costs, morbidity and mortality. Our aim was to assess risk factors for urological complications in deceased donor kidney transplantation. Between January 2000 and December 2011, 566 kidney transplantations were performed with deceased donor kidneys. Recipients were divided in a group with, and a group without urological complications, defined as the need for a percutaneous nephrostomy catheter or surgical revision of the ureteroneocystostomy. Univariate and multivariate analyses were performed. Univariate analysis showed increased number of male donors (p = 0.041), male recipients (p = 0.002), pre-emptively transplanted recipients (p = 0.007), and arterial reconstructions (p = 0.004) in the group with urological complications. Less urological complications occurred in recipients on hemodialysis (p = 0.005). More overall surgical interventions (p<0.001), surgical site infections (p = 0.042), urinary tract infections (p<0.001) and lymphoceles (p<0.001) occurred in the group with urological complications. Multivariate analysis showed that male recipients (p = 0.010) and arterial reconstructions (p = 0.019) were independent risk factors. No difference was found between both groups in patient or graft survival. In conclusion, recipient male gender and arterial reconstruction are independent risk factors for urological complications after deceased donor kidney transplantation. Nevertheless, graft and recipient survival is not different between both groups.

[Allogeneic kidney transplantation. Preoperative, perioperative and postoperative management]

Allogeneic renal transplantation is the best treatment for many patients with chronic renal failure and end-stage kidney disease. Especially the health-related quality of life markedly improves after renal transplantation and the side effects of dialysis treatment as well as the progression of organ and tissue deterioration related to renal failure which are not treated effectively by dialysis are greatly reduced. To achieve good results of renal transplantation, however, the best possible preoperative as well as perioperative and postoperative conditions have to be established and patients on waiting lists need to be well prepared. Interdisciplinary patient care is needed before and after renal transplantation in order to achieve durable and long-term success of renal transplantation.