Endoscopic Management of Urologic Complications Following Renal Transplantation: Impact of Ureteral Anastomosis

Evaluation of the Effectiveness of Interventions on Nephrolithiasis in Transplanted Kidney

CONTEXT

De Novo nephrolithiasis in renal transplant can have severe consequences since renal transplantation involves a single functioning kidney with medical and anatomical specificities (heterotopic transplantation on iliac vessels, immunosuppressive treatments, and comorbidities).

OBJECTIVE

To systematically review all available evidence on the prevalence of de novo nephrolithiasis in renal transplant, presentation, and stone characteristics, and to report in a meta-analysis the efficacy of stone treatments (extracorporeal shock wave lithotripsy [ESWL], medical treatment, percutaneous nephrolithotomy [PCNL], open surgery, and ureteroscopy).

EVIDENCE ACQUISITION

Medline, Embase, and the Cochrane Library were searched up to November 2021 for all relevant publications reporting the management of de novo nephrolithiasis in renal allografts. The primary outcome was stone-free rate (SFR) at 3 mo. Secondary outcomes included prevalence, stone characteristics (size, density, and composition), symptoms on presentation, need for drainage, complications, and recurrence. Data were narratively synthesized in light of methodological and clinical heterogeneity, and a meta-analysis was performed for SFR. The risk of bias of each included study was assessed.

EVIDENCE SYNTHESIS

We included 37 retrospective studies with 553 patients and 612 procedures; of the 612 procedures 20 were antegrade ureteroscopy, 154 retrograde ureteroscopy, 118 PCNL, 25 open surgery, 155 ESWL, and 140 surveillance/medical treatment. The prevalence of nephrolithiasis in renal transplant was 1.0%. The mean stone size on diagnosis was 11 mm (2-50). The overall SFR at 3 mo was 82%: 96% with open surgery, 95% with antegrade ureteroscopy, 86% with PCNL, 81% with retrograde ureteroscopy, and 75% with ESWL.

CONCLUSIONS

De novo nephrolithiasis in renal transplant is an infrequent condition. A high SFR were obtained with an antegrade approach (ureteroscopy, PCNL, and open approach) that should be considered in renal transplant patients owing to the heterotopic position of the renal graft. The choice of technique was correlated with stone size: generally ureteroscopy and ESWL for stones 11-12 mm (mean stone size) versus PCNL and open surgery for 17-25 mm stones.

PATIENT SUMMARY

De novo nephrolithiasis in renal transplants is an infrequent situation that can have severe consequences on the function of the renal graft. We evaluated the efficacy of each treatment and noted that antegrade approaches (open surgery, percutaneous nephrolithotomy, and antegrade ureteroscopy) were associated with the highest stone-free rate. As opposed to the management of nephrolithiasis in native kidney, an antegrade approach should be considered more in renal transplant patients.

A STENTLESS MODIFIED LICH-GREGOIR TECHNIQUE FOR SAFE EARLY BLADDER CATHETER REMOVAL IN LIVING AND DECEASED KIDNEY TRANSPLANTS

OBJECTIVES

To describe a stentless modified Lich-Gregoir technique (mLG) for ureteroneocystostomy in renal transplantation (RT), with early bladder catheter (BC) removal (under 48 hours), and compare the postoperative results with those of the traditional technique (LG) with routine bladder catheter removal (4 to 5 days). The modification consists of maintaining a thin layer of detrusor fibers covering the bladder mucosa during dissection, which is incorporated into the anastomosis to reinforce the ureteroneocystostomy.

MATERIALS AND METHODS

This retrospective cohort study compared the postoperative outcomes of 100 consecutive patients who underwent mLG with early removal of BC between October 2018 to November 2019 with those of a historical cohort of 165 consecutive patients transplanted using stentless LG and routine removal of BC, who underwent surgery between July 2017 and September 2018. All transplants were performed by the same surgeon. Follow-up was 6 months.

RESULTS

Demographic characteristics were comparable, although patients in the mLG group had a higher mean preoperative urine volume (911±753.8mL vs. 629±638.6mL, p=0.016). Patients in the mLG group successfully underwent early BC removal (2.2±0.9 vs. 4.8±4.8 days, p<0.001), with no differences in the incidence of surgical or clinical complications, including urine leaks (1 vs. 3%, p=0.284). In addition, mLG patients presented a shorter mean length of hospital stay (6.5±5.0 vs. 7.1±6.2 days, p=0.023).

CONCLUSION

This stentless modified Lich-Gregoir technique enables safe early bladder catheter removal and is associated with reduced hospital length of stay.

Results of a previously unreported extravesical ureteroneocystostomy technique without ureteral stenting in 500 consecutive kidney transplant recipients

Urologic complications can still occur following kidney transplantation, sometimes requiring multiple radiological and/or surgical procedures to fully correct the problem. Previously proposed extravesical ureteral reimplantation techniques still carry non-negligible risks of the patient developing urologic complications. About 10 years ago, a new set of modifications to the Lich-Gregoir technique was developed at our center, with the goal of further minimizing the occurrence of urologic complications, and without the need for initial ureteral stent placement. It was believed that an improvement in the surgical technique to minimize the risk of developing urologic complications was possible without the need for stent placement at the time of transplant. In this report, we describe the advantages of this technique (i.e., mobilized bladder, longer spatulation of the ureter, inclusion of bladder mucosa with detrusor muscle layer in the ureteral anastomosis, and use of a right angle clamp in the ureteral orifice to ensure that it does not become stenosed). We also retrospectively report our experience in using this technique among 500 consecutive (prospectively followed) kidney transplant recipients transplanted at our center since 2014. During the first 12mo post-transplant, only 1.4%(7/500) of patients developed a urologic complication; additionally, only 1.0%(5/500) required surgical repair of their original ureteroneocystostomy. Five patients(1.0%) developed a urinary leak, with 3/5 having distal ureteral necrosis, and 1/5 subsequently developing a ureteral stricture. Two other patients developed ureteral stenosis, one due to stricture and one due to ureteral stones. These overall results are excellent when compared with other reports in the literature, especially those in which routine stenting was performed. In summary, we believe that the advantages in using this modified extravesical ureteroneocystostomy technique clearly help in lowering the early post-transplant risk of developing urologic complications. Importantly, these results were achieved without the need for ureteral stent placement at the time of transplant.

Initial Experience in the Use of Novel Auto-expandable Metal Ureteral Stent in the Treatment of Ureter Stenosis in Kidney Transplanted Patients

INTRODUCTION

Ureter stenosis in renal transplantation patients is a relatively frequent complication that negatively conditions graft evolution. The use of ureteral stents is a valid treatment alternative to the use of double-J catheters in patients for whom surgery is not contemplated or after surgical recurrence. We present our initial experience with five patients treated using this technique.

MATERIALS AND METHODS

We describe a total of five patients with ureteral stenosis after renal transplantation who were treated using ureteral stent model UVENTA (Taewoong Medical, Seoul, Korea) in our center. The median follow-up was 18 months (range, 4 to 38 months). We describe the clinical history of patients and previous treatments on ureteral stenosis. The technical procedure of placement is described. The clinical course is analyzed by measurement of renal function and imaging tests, as well as post-stent complications. Survival of the renal graft is evaluated.

RESULTS

The procedure could be completed in all patients without complications. The technique was effective in all patients, with correction of creatinine value and hydronephrosis during the renal ultrasound test. One patient suffered a urinary tract infection episode associated with the use of the ureteral stent. One patient suffered the loss of the renal graft secondary to the development of cryoglobulins. One hundred percent of the ureteral stents are functioning as of the writing of this article.

CONCLUSIONS

In renal transplantation patients with ureter stenosis, metallic stents are a useful technique with low morbidity and associated complications.

Ureteral Stenosis After Renal Transplantation-A Single-Center 10-Year Experience

BACKGROUND

Kidney transplantation (KT) is the definitive treatment for ESRD. Ureteral stenosis (US) is one of the most common urologic complications and has been reported in 2.6%-15% of KTs.

METHODS

We reviewed data for 973 consecutive KT procedures performed at our center from January 2004 to September 2014, with evaluation of US management and recurrence rate.

RESULTS

The 973 KTs were performed with the use of the direct ureterovesical (UV) implantation Paquin technique, and the mean follow-up time was 44.3 ± 30.2 [range, 3-111] months. During this period, 33 cases of US (3.39%) were reported. The interval from KT to US diagnosis was 10.6 ± 23.0 (range, 0.5-98.0) months. The majority of the US cases were located in the distal ureter and UV junction (83.9%), with only 2 cases of middle ureter stenosis and 2 cases of ureteropelvic junction. Mean US length was 2.5 ± 1.9 (range, 1.0-10.0) cm. Surgical management and global and treatment-specific recurrence rates were reviewed. Primary surgical treatment recurrence rate was higher for the endoscopic approach, with a mean global time from treatment to US recurrence of 6.9 ± 16.3 (range, 0-65) months and a median of 2.0 months. Open surgical approach was the main recurrence treatment option (74%). There were 2 cases of graft loss. Success rate evaluation of overall and treatment-specific primary surgical management did not reveal significant differences (P > .05) according to stenosis length (<1.5, 1.5-3.0, or >3.0 cm), time between transplant and stenosis (≤3, 3-12, or >12 mo), or stenosis location (distal, middle, or upper ureter). However, there was clearly a trend to higher success rate in smaller stenosis (<1.5 cm) and early management (≤3 mo), particularly with the use of balloon dilation.

CONCLUSIONS

US management should be decided on a case-by-case basis according to clinical characteristics, treatment-specific recurrence rate, and previous surgical options.

Optimal management of distal ureteric strictures following renal transplantation: a systematic review

Our objective was to define optimal management of distal ureteric strictures following renal transplantation. A systematic review on PubMed identified 34 articles (385 patients). Primary endpoints were success rates and complications of specific primary and secondary treatments (following failure of primary treatment). Among primary treatments (n = 303), the open approach had 85.4% success (95% CI 72.5-93.1) and the endourological approach had 64.3% success (95% CI 58.3-69.9). Among secondary treatments (n = 82), the open approach had 93.1% success (95% CI 77.0-99.2) and the endourological approach had 75.5% success (95% CI 62.3-85.2). The most common primary open treatment was ureteric reimplantation (n = 33, 81.8% success, 95% CI 65.2-91.8). The most common primary endourological treatment was dilation (n = 133, 58.6% success, 95% CI 50.1-66.7). Fourteen complications, including death (4 weeks post-op) and graft loss (12 days post-op), followed endourological treatment. One complication followed open treatment. This is the first systematic review to examine the success rates and complications of specific treatments for distal ureteric strictures following renal transplantation. Our review indicates that open management has higher success rates and fewer complications than endourological management as a primary and secondary treatment for post-transplant distal ureteric strictures. We also outline a post-transplant ureteric stricture evaluation and treatment algorithm.

[Conservative management of upper tract urinary fistulae using ureteral trans-vesico-parietal stent]

OBJECTIVES

Ureteral stents and ureteral catheters externalized through the urethra are not ideal solutions to manage complicated upper urinary tract fistulae. We sought an effective method of drainage, minimally invasive, reproducible allowing a rapid patient's discharge.

PATIENTS AND METHODS

Between November 2013 and February 2015, an ureteral stent was exteriorized in trans-vesico-parietal by an endoscopic and percutaneous access in patients with complicated upper urinary tract fistulae. Monitoring of tolerance, complications and urinary fistula healing was performed.

RESULTS

Nine consecutive patients had an ureteral stent exteriorized in trans-vesico-parietal to manage complicated upper urinary tract fistulae. There was no failure in introducing the catheter, or postoperative complication. Catheters were left in place on average 36.1days (24-55). The patients were able to return home with the catheter in place in 77.8% of cases. The tolerance of the catheter was good. All fistulae were able to be treated conservatively at the end of the drainage period.

CONCLUSION

Trans-vesico-parietal ureteral catheters enable efficient and reproducible conservative treatment of upper tract urinary fistulae regardless of their cause.

LEVEL OF EVIDENCE

5.

Comparative urologic complications of ureteroneocystostomy in kidney transplantation: transvesical Leadbetter-Politano versus extravesical Lich-Gregoir technique

BACKGROUND

The incidence of urologic complications after kidney transplantation remains high despite improvements in diagnosis and operative techniques. Urinary tract reconstruction is usually done by ureteroneocystostomy (UCNS), and several techniques are available. In this study, we evaluated the outcomes of 2 different UCNS techniques performed in our department, the transvesical Leadbetter-Politano (L-P) and the extravesical Lich-Gregoire (L-G) technique.

MATERIAL AND METHODS

We evaluated the outcomes of 2 different UCNS techniques, L-P versus L-G, performed in our department between July 1, 2006, and December 31, 2011. During this period, we performed 524 consecutive renal transplantations-264 cases using the L-P technique (50.3%) and 260 cases with L-G technique (49.7%). Renal grafts were obtained from cadaveric donors in 146 cases (27.86%) and from living-related donors in 378 cases (72.14%). Recipient mean age was 35.64 years and the male to female ratio was 1.63:1.

RESULTS

Urologic complications after kidney transplantation occurred in 22 cases in the L-P UCNS group (8.33%). The most common complications were ureteral stenosis (3.41%) and leakage (2.65%). Other complications recorded were lymphoceles (1.89%) and hematoma with secondary ureteral obstruction (0.38%). Compared with the L-P UCNS technique, the L-G technique was associated with fewer overall complications (6.15% vs 8.33%; P = .06), a lesser rate of ureteral stenosis (2.31% vs 3.41%; P = .08), and a similar rate of leakage. However, statistical analysis revealed no differences between the 2 techniques (P = .06). In addition, we did not note any differences in graft and patient survival between the 2 groups.

CONCLUSIONS

In our study, the extravesical L-G technique has a lower complication rate compared with transvesical L-P procedure, but without statistical differences. Furthermore, the L-G technique is easier and faster to perform, it avoids a separate cystotomy, and requires a shorter ureteral length. In conclusion, we recommend L-G technique as technique of choice in kidney transplantation.

Ureterovesical anastomotic techniques for kidney transplantation: a systematic review and meta-analysis

No consensus exists about which ureterovesical anastomosis technique to use for kidney transplantation. The aim of this systematic review was to compare the existing techniques in relation to the risk of urological complications. All studies that compared ureterovesical anastomotic techniques in kidney transplantation were included. Study endpoints were urinary leakage, ureteral stricture, vesicoureteral reflux and hematuria. Subanalyses of stented and nonstented techniques were performed. Two randomized clinical trials and 24 observational studies were included. Meta-analyses were performed on the Lich-Gregoir (LG) versus Politano-Leadbetter (PL) techniques and LG versus U-stitch (U) techniques. Compared with the PL technique, the LG technique had a significantly lower prevalence of urinary leakage (risk ratio (RR): 0.47, 95% confidence interval (CI): 0.30 to 0.75) and a significantly lower prevalence of hematuria when compared with both PL and U techniques (RR: 0.28, 95% CI: 0.16 to 0.49 and RR: 0.23, 95% CI: 0.11 to 0.50, respectively), regardless of ureteral stenting. There was no difference in the prevalence of ureteral strictures or vesicoureteral reflux between the various techniques. Of the three most frequently used ureterovesical anastomotic techniques, the LG technique results in fewer urological complications than the PL and U techniques.

Intravesical versus extravesical ureteroneocystostomy in kidney transplantation: a systematic review and meta-analysis

Urological complications are still a major problem postoperatively with a reported incidence of up to 30%, associated with significant morbidity, mortality, prolonged hospital stay and high medical costs. To date, there is no evidence favouring either an extravesical or an intravesical approach. The purpose of this systematic review and meta-analysis is to determine if an intravesical or extravesical anastomosis in kidney transplantation is to be preferred. Comprehensive searches were conducted in PubMed, Embase and the Cochrane Library. Reference lists were searched manually. The methodology was in accordance with the PRISMA statement. Two randomized controlled trials and seventeen cohort studies were identified. Based on the meta-analysis, outcome was in favour of the extravesical anastomosis. A relative risk (RR) for stenosis of 0.67 (confidence interval (CI), 0.48-0.93; p = 0.02), for leakage 0.55 (CI 0.39-0.80; p = 0.001) for the total number of urological complications 0.56 (CI 0.41-0.76; p < 0.001) and for haematuria of 0.41 (CI 0.22-0.76; p = 0.005) was demonstrated. Based on our results, we conclude that there is evidence in favour of the extravesical ureteroneocystostomy for having a smaller amount of urological complications in kidney transplantation.

Impact of surgeon experience on complication rates and functional outcomes of 484 deceased donor renal transplants: a single-centre retrospective study

OBJECTIVE

To determine how postoperative and functional outcomes after deceased donor renal transplantation (DDRT) are related to surgeon experience.

PATIENTS AND METHODS

The outcomes of 484 adult DDRT performed by 13 urological surgeons were retrospectively reviewed. After completion of a staged renal transplant training programme under supervision of an attending urological transplant surgeon, the 13 surgeons were either assigned to the inexperienced group (n = 8) or the experienced group (n = 5). Surgeons in the experienced group had performed more than 30 unsupervised DDRT in a standard fashion with routine ureteric stenting. Between 1988 and 2005, inexperienced surgeons performed 152 DDRT, whereas experienced surgeons performed 332 DDRT.

RESULTS

Patient and graft survival at 2 hyears were 98% and 94.7%, respectively. Early graft loss in five recipients was unrelated to surgeon experience. Delayed graft function occurred in 29% of cases and median 1-year serum-creatinine was 1.48 mg/dL, with no difference between surgeon groups. Postoperative bleeding and lymphocele formation were the most frequent surgical complications, with an equal distribution between groups. Ureteric complications had a significantly higher incidence among inexperienced surgeons (6.6% versus 2.7%; P = 0.04).

CONCLUSION

We conclude that DDRT as performed by inexperienced urological renal transplant surgeons has both acceptable short- and long-term outcomes.