Endourologic implants to treat complex ureteral stenosis after kidney transplantation

Post-Transplant Ureteric Stricture Managed By Extra-Anatomical Stenting With Modification on the Originally Described Stent Location: A Case Report

Ureteric strictures are a relatively uncommon complication following renal transplant, which may be managed endoscopically or surgically by repairing the stricture. Extra-anatomical bypass is a useful procedure in complex cases that bypasses the ureter by creating a subcutaneous route, although it is uncommonly used given its rare indication. We report a case of renal transplant ureteric stricture, in which we utilized a modified extra-anatomical stenting technique with a Detour® stent to avoid the fibrotic planes surrounding the lateral aspect of the kidney graft.

Temporary Covered Metallic Ureteral Stent Placement for Ureteral Strictures following Kidney Transplantation: Experience in 8 Patients

This brief report presents 8 patients with silicone-covered metallic stent placement for ureteral strictures refractory to double-J stent placement, following kidney transplantation. Stent removal was successfully performed in 7 patients via antegrade (n = 4) or retrograde (n = 3) access 6 weeks to 6 months after stenting for elective removal (6-month interval, n = 3), urothelial hyperplasia (n = 2), or stent migration (n = 2), and their mean primary ureteral patency after stent removal was 15.4 months (range, 2-27 months). Hematuria (n = 2) and pain (n = 3) occurred, but resolved within 1 week. One stent was removed during reconstructive surgery. During follow-up of mean 22.6 months after stent removal, ureteral strictures recurred in 2 patients.

Long-term results of the treatment of complex ureteral stenosis with extra-anatomic ureteral bypasses

Introduction

Complex ureteral obstruction is a pathology that has always been a challenge for the urologist, especially in patients with high surgical risk or with a short life expectancy.

Material and methods

Between 2002 and 2017, 13 extra-anatomical bypasses were placed. A descriptive retrospective study was carried out. An analysis of the permeability time of the prosthesis was performed using Kaplan-Meyer curves. Demographic and etiological characteristics as well as early and late complications were analysed.

Results

Etiologies were benign in 39% (including 3 transplant recipients) and malignant in 69%. Permeability rates were 90.9% at each of 12, 24 and 48 months, respectively, and 75.8% at 60 months. There were no deaths in the early postoperative period, nor intraoperative complications. The most frequent complications were infections. Three of them were associated with bypass extrusion, which needed to be removed. A total of 5 prosthesis had to be removed. 40% of the patients did not present complications.

Conclusions

The extra-anatomical ureteral bypass is an alternative to permanent nephrostomy in the treatment of complex ureteral strictures. Their patency rates after long-term follow-up vary from 90% to 75% at 48 and 60 months, respectively. Their complication rates can be considered acceptable in the patients’ clinical contexts.

Kidney autotransplantation: long-term outcomes and complications. Experience in a tertiary hospital and literature review

OBJECTIVE

To analyze indications, surgical technique, complications and long-term outcomes of kidney autotransplantation (KAT) after 26-year experience at a single institution.

MATERIALS AND METHODS

A retrospective observational study of patients who underwent KAT at our institution (January 1990-December 2016) was carried out. Data collected included indications, surgical technique, complications (Clavien-Dindo), hospital stay and long-term outcomes. Literature review was performed through MEDLINE and ClinicalKey databases including "kidney," "renal," "autotransplantation" and "autograft."

RESULTS

Fifteen patients underwent a KAT, with a mean age of 41 years (range 34-59). Indications were vascular abnormalities in 8 cases and ureteral injury in 7. Nephrectomy was performed through laparoscopy in 2 cases (13.3%) and open in 13 (86.7%). Vascular grafts to reperfuse the kidney were used in 8 patients, and ureteral reimplantation was performed in 11 cases. Mean hospital stay was 9.1 days (range 3-20). Seven patients (46.7%) developed postoperative complications: 6 minor (Clavien I-II) and 1 major (Clavien III). After a mean follow-up of 73.1 months (range 7-312), 80% of the patients have a functioning graft. Most common indication reported in the literature is ureteral stricture, especially in the most recent years. Graft survival is variable, and complications are frequent, but usually minor.

CONCLUSIONS

KAT is an effective treatment for complex ureteral lesions and kidney vascular abnormalities, with good results in the long term. Surgical complications are frequent, but usually minor. As a challenging surgery, it should be performed by experienced kidney transplant surgeons. Complex and proximal ureteral injuries are nowadays the main indication of this procedure.

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.

Ureteric reconstruction for the management of transplant ureteric stricture: a decade of experience from a single centre

This study was conducted to review the outcomes of patients who had undergone surgical repair of a ureteric stricture following renal transplantation. All patients who developed a ureteric stricture and underwent ureteric reconstruction following renal transplantation, between December 2003 and November 2013, were reviewed. One thousand five hundred and sixty renal transplants were performed during the study period. Forty patients required surgical repair of a ureteric stricture (2.5%, 25 male, median age 48 [14-78]). The median time to stricture was 3 [1-149] months. 19 patients were reconstructed by reimplantation to the bladder, 18 utilized a Boari flap, two were a pre-existing ileal conduit and one was an anastomosis to a native ureter. In one patient, reconstruction was impossible and consequently an extra-anatomic stent was used. Two patients required re-operation for restricture and kinking. Median serum creatinine at 12 months following surgery was 148 [84-508] μmol/l. There was no 90-day mortality. Eleven grafts were lost at the time of this study, a median time of 11 [1-103] months after reconstruction. The incidence of ureteric stricture following renal transplant is low. Surgical reconstruction of the transplant ureter is the optimal treatment and is successful in the majority of patients.

Surgical management of early and late ureteral complications after renal transplantation: techniques and outcomes

BACKGROUND

In this study, we present our experience with ureteral complications requiring revision surgery after renal transplantation and compare our results to a matched control population.

METHODS

We performed a retrospective analysis of our database between 1997 and 2012. We divided the cases into early (<60 d) and late repairs. Kaplan-Meier and Cox proportional hazards models were used to compare graft survival between the intervention cohort and controls generated from the Scientific Registry of Transplant Recipients data set.

RESULTS

Of 2671 kidney transplantations, 51 patients were identified as to having undergone 53 ureteral revision procedures; 43.4% of cases were performed within 60 d of the transplant and were all associated with urinary leaks, and 49% demonstrated ureteral stenosis. Reflux allograft pyelonephritis and ureterolithiasis were each the indication for intervention in 3.8%; 15.1% of the lesions were located at the anastomotic site, 37.7% in the distal segment, 7.5% in the middle segment, 5.7% proximal ureter, and 15.1% had a long segmental stenosis. In 18.9%, the location was not specified. Techniques used included ureterocystostomy (30.2%), ureteroureterostomy (34%), ureteropyelostomy (30.1%), pyeloileostomy (1.9%), and ureteroileostomy (3.8%). No difference in overall graft survival (HR 1.24 95% CI 0.33-4.64, p = 0.7) was detected when compared to the matched control group.

CONCLUSION

Using a variety of techniques designed to re-establish effective urinary flow, we have been able to salvage a high percentage of these allografts. When performed by an experienced team, a ureteric complication does not significantly impact graft survival or function as compared to a matched control group.

Extra-anatomic stent (EAS) as a salvage procedure for transplant ureteric stricture

Ureteric stricture is the most common urological complication following renal transplantation. Management often involves endo-urological interventions and open surgery. The definitive treatment is surgical reconstruction to restore continuity. Where this is not possible or contra-indicated and a stent cannot be placed in the ureter, an extra-anatomic stent (EAS) could be used to bypass a complete ureteric obstruction. Using an existing nephrostomy tract, a percutaneous stent is placed in the kidney and is tunneled under the skin into the bladder establishing extra-anatomical urinary drainage. We report the use of a novel EAS system in a patient with transplant ureteric stricture when antegrade stent placement or surgical reconstruction was not possible.

[Long-term results for subcutaneous Detour® prosthesis for ureteral obstruction: experiences of implantation, aftercare and management of complications]

BACKGROUND

We present the long-term results of implementation of the Detour® prosthesis as an alternative to established methods of surgical, percutaneous or internal urinary diversion.

PATIENTS AND METHODS

Between 2004 and 2012 a total of 40 prostheses were implanted in 31 patients (mean age 65 years) with ureteral strictures of various origins. In the follow-up the patients underwent examinations and completed questionnaires.

RESULTS

The average follow-up was 23 months (range 1-92 months). Sonographic examinations showed no urinary retention in 38 out of 40 implanted systems. The retention values were stable in 19 patients, improved in 7 and worse in 3. The quality of life (QoL) was high (EORTC QLQ-C30 90%). Intraoperative complications were 2 intestinal lesions and 3 bleeding of the renal-pelvic system. Postoperative urinary tract infections and wound complications were encountered. In the long-term course three infected hydronephroses occurred which were treated and cured with antibiotics and temporary nephrostomy and 4 systems were explanted, including 2 exchanges.

CONCLUSIONS

The system may be considered for patients with ureteral strictures with palliative and curative intent. There were no significant disadvantages in comparison with established methods. There were fewer risks in implantation and complications were manageable. The quality of life was significantly improved.

Endourological management of ureteric strictures after kidney transplantation: Stenting the stent

The incidence of ureteric obstruction after kidney transplantation is 3–12.4%, and the most common cause is ureteric stenosis. The standard treatment remains open surgical revision, but this is associated with significant morbidity and potential complications. By contrast, endourological approaches such as balloon dilatation of the ureter, ureterotomy or long-term ureteric stenting are minimally invasive treatment alternatives. Here we discuss the available minimally invasive treatment options to treat transplant ureteric strictures, with an emphasis on long-term stenting. Using an example patient, we describe the use of a long-term new-generation ureteric metal stent to treat a transplant ureter where a mesh wire stent had been placed 5 years previously. The mesh wire stent was heavily encrusted throughout, overgrown by urothelium and impossible to remove. Because the patient had several previous surgeries, we first considered endourological solutions. After re-canalising the ureter and mesh wire stent by a minimally invasive procedure, we inserted a Memokath® (PNN Medical, Kvistgaard, Denmark) through the embedded mesh wire stent. This illustrates a novel method for resolving the currently rare but existing problem of ureteric mesh wire stents becoming dysfunctional over time, and for treating complex transplant ureteric strictures.

Retrograde balloon dilation >10 weeks after renal transplantation for transplant ureter stenosis - our experience and review of the literature

Objective

Despite many efforts to prevent ureteric stenosis in a transplanted kidney, this complication occurs in 3–5% of renal transplant recipients. Balloon dilatation (BD) is a possible minimally invasive approach for treatment, but reports to date refer only to the antegrade approach; we analysed our experience with retrograde BD (RBD) and reviewed previous reports.

Patients and methods

From October 2008 to February 2011, eight patients after renal transplantation (RTX) underwent RBD for transplant ureteric stenosis at our hospital. We retrospectively analysed the outcome and reviewed previous reports.

Results

The eight recipients (five men and three women; median age 55 years, range 38–69) were treated with one or two RBDs for transplant ureteric stenosis. There were no complications. The median (range) time after RTX was 4.5 (2.5–11) months. Long-term success was only achieved in one recipient, while five patients were re-operated on (three with a new implant, two by replacement of transplanted ureter with ileum) after a median (range) of 2.8 (0.7–7.0) months after unsuccessful RBD(s). For two recipients the success remained unclear (one graft loss due to other reasons, one result pending). When the first RBD was unsuccessful there was no improvement with a second.

Conclusion

RBD is technically feasible, but our findings and the review of previous reports on antegrade ureteric dilatation suggest that the success rate is low when the ureter is dilated at ⩾10 weeks after RTX. From our results we cannot recommend RBD for transplant ureteric stenosis at ⩾10 weeks after RTX, while previous reports show favourable results of antegrade BD in the initial 3 months after RTX.