Balloon dilation of ureteral strictures after renal transplantation

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

Background

Long-term outcomes of kidney transplantation recipients with percutaneous ureteral management of transplant ureteral complications are not well characterized.

Methods

Electronic 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.

Results

Kaplan- 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%).

Conclusions

Kidney 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.

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.

Use of Self-Expanding Metallic Ureteral Stents in the Secondary Treatment of Ureteral Stenosis Following Kidney Transplantation

INTRODUCTION

To evaluate the safety and efficacy of self-expanding metal stents in the treatment of ureteral stenosis following kidney transplantation.

MATERIALS AND METHODS

Seven patients who developed benign stenosis after kidney transplantation were treated by a self-expanding metallic stent implantation from June 2007 to March 2014. All patients had undergone at least one open surgical procedure and one endourologic procedure for treatment of the stenosis. The extent of stenosis varied from 1.2 to 3.7 cm. Ultrasonography, urography, diuretic renography, and urine culture were performed every 3 months after stent insertion. Ureteroscopic examination was performed when needed.

RESULTS

Stent placement was technically effective in all cases. The mean operative time was 37 minutes (range, 26-59 minutes). Lower urinary-tract symptoms and the ipsilateral flank pain were common early-stage complications and were greatly relieved after an average of 3 months. The mean follow-up duration was 38 months (range, 13-86 months), and no stent migration or fragmentation was observed. Urothelial hyperplasia occurred in only one patient and was effectively managed with a Double-J stent. Five patients had normal stable renal function; the remaining two had impaired renal function, including one patient with a preoperative renal failure who required dialysis at the end of the follow-up period (36 months).

CONCLUSIONS

As an alternative to open surgery, implantation of a self-expanding metal stent is a safe and effective treatment for ureteral stenosis in patients who have undergone kidney transplantation.

Urological Consequences following Renal Transplantation: A Review of the Literature

Renal transplant (RT) represents the treatment of choice for end-stage renal disease (ESRD) but harbours a wide range of possible complications and therapeutic challenges of urological competence. Dialysis years and clinical medical background of these patients are risk factors for sexual dysfunction and lower urinary tract symptoms (LUTS). On the contrary, RT itself may have a number of possible surgical complications such as ureteral stenosis and urinary leakage, while immunosuppressive treatment is a known risk factor for de-novo malignancies.

The present review describes the main urologic problems of RT patients and their up-to-date treatment options according to the most recently available literature evidences.

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.

Native ureteropyelostomy in the treatment of obstructive uropathy in adult renal transplant. Experience and technical alternatives

OBJECTIVE

To analyze and evaluate our experience in surgical treatment with the open approach of the complex ureteral stenosis after adult kidney transplantation in a tertiary level hospital in the last seven years. We have reviewed the different surgical options used.

PATIENTS AND METHODS

A total of 589 consecutive adult renal transplants were performed from January 2005 to December 2012. Of these, 1.1% showed some degree of symptomatic obstructive uropathy which after initial urinary diversion required open surgical approach using the ipsilateral or contralateral native urinary tract. Characteristics of the patient, clinical examinations performed and surgical technique performed as well as their results are presented.

RESULTS

During the period under review, in 5 men and 2 women who had ureteral stenoses after renal transplant, 7 reparative surgeries were performed by open ureteropyelostomy, using ipsilateral native ureter in 6 cases and contralateral ureter in the remaining case. In one case, uretero-calicial anastomosis was performed due to severe pyelic shrinkage. There were no significant complications. Native kidney nephrectomy was not required for further complications. All the patients operated on had optimum plasma creatinine levels with resolution of previous dilatation.

CONCLUSIONS

The initial percutaneous nephrostomy followed by open surgical repair using native ureter represents a definitive, valid and optimal alternative in terms of safety and preservation of renal function.

Current status of minimally invasive endoscopic management of ureteric strictures

Endourological techniques are used more often nowadays in the treatment of ureteric strictures of various etiologies. Advances in technology have provided new tools to the armamentarium of the endoscopic urological surgeon. Numerous studies exist that investigate the efficiency and safety of each of the therapeutic modalities available. In this review, we attempt to demonstrate the available and contemporary evidence supporting each minimally invasive modality in the management of ureteric strictures.

Classification of ureteral stenosis and associated strategy for treatment after kidney transplant

OBJECTIVES

Ureteral stenosis is a common complication after a kidney transplant. Treatment for ureteral stenosis ranges from interventional procedures to open surgery. The aim of this study is to present classification for ureteral stenosis and recommend the targeted strategy for effective treatment.

MATERIALS AND METHODS

Twelve cases of ureteral stenosis were diagnosed among 193 kidney transplants, of which 91 were from a live donor and 102 from a deceased donor. The mean age was 46.22 ± 13.23 years. The diagnosis of ureteral stenosis includes serum creatinine elevation, hydronephrosis, and presence of stricture on a pyelogram. The criterion for classification is based on the severity of stricture.

RESULTS

One of ureteral stenoses was classified as grade 1, six were grade 2, and five were grade 3. Of 12 cases, 10 were live-donor kidney transplant, 4 had lymphocele, and 2 had a hematoma after transplant. The corresponding strategy for each grade of ureteral stenosis is as follows: grade 1, ureteral stent reinsertion; grade 2, cutting balloon dilatation or endoscopic incision of stenosis; grade 3, open surgery urinary tract reconstruction. All cases were successfully treated using these strategies.

CONCLUSIONS

This classification of ureteral stenosis provides guidance for effective management and avoids unnecessary procedures. In this series, ureteral stenosis was significantly associated with a live donor and surgical complications.

Percutaneous ureteral interventions

Urinary strictures are commonly managed by interventional radiologists and can result from both benign and malignant etiologies. Many patients end up with lifelong catheters. Although stricture dilation is commonly unsuccessful, some patients can eventually become catheter free. This review describes current outcomes with a variety of dilation and stenting techniques. Management of complex ureteral and urinary complications is also reviewed, including ureteral/arterial fistulas and ureteral embolization for permanent diversion.

Endourologic implants to treat complex ureteral stenosis after kidney transplantation

OBJECTIVE

To evaluate the safety and efficacy of nitinol stents and the Detour extra-anatomical ureteral bypass graft in treatment of ureteral stenosis after kidney transplantation.

PATIENTS AND METHODS

Eighteen kidney transplant recipients with complex stenosis caused by failure of primary treatment or with high surgical risk or a poorly functioning graft (serum creatinine concentration >2.5 mg/dL) were treated using antegrade percutaneous implantation of nitinol stents (n = 16) or extra-anatomical ureteral bypass grafts (n = 3); 1 patient was treated with both techniques.

RESULTS

Mean (range) follow-up of ureteral stents was 51.2 (3-118) months. Patency rate at last follow-up, resumption of dialysis therapy, or death was 75% (12 of 16 patients). In 4 patients (25%), stent occlusion developed, which was treated using a double-J catheter in 2 patients, stent removal and pyeloureterostomy using the native ureter in 1 patient, and implantation of an extra-anatomical bypass graft in 1 patient. Mean follow-up in patients with extra-anatomical ureteral bypass grafts was 32 (8-64) months. One patient developed a urinary tract infection, and another had encrustation with obstruction.

CONCLUSIONS

Use of nitinol ureteral stents and extra-anatomical ureteral bypass grafts is a safe and effective alternative to surgery for treatment of post-kidney transplantation ureteral stenosis in patients with chronic graft dysfunction, those at high surgical risk, and those in whom previous surgical treatment has failed.

Ureteroscopic management of urological complications after renal transplantation

OBJECTIVE

To determine the feasibility, safety and efficacy of diagnostic and therapeutic ureteroscopy in renal allograft ureters.

MATERIAL AND METHODS

We reviewed 1560 consecutive renal allografts performed between June 1989 and February 2002. A total of 28 patients (1.8%) had indications for an endoscopic procedure on the allograft ureter, as follows: obstructive ureteral calculi with a history of failed extracorporeal shock-wave lithotripsy, n=6; suspected ureteral stricture, n=3; upwardly migrated ureteral stents, n=9; and ureteral stricture at the ureteroneocystostomy site, n=10. Ureters were anastomosed to the bladder using the Leadbetter-Politano and Lich-Gregoire methods in six and 22 cases, respectively. Ureteroscopies were performed with a semi-rigid 9.8 F Wolf ureteroscope.

RESULTS

Identification of the ureteral orifice and insertion of a guide-wire into it was successful in 19 cases (68%). If we exclude the 10 patients with ureteral stricture, ureteroscopy was successful in 13/18 cases (72%). Four ureteral calculi (67%) were removed with the ureteroscope. Seven out of nine migrated stents (78%) were retrieved. Four patients with ureteral stricture at the ureteroneocystostomy site (40%) underwent successful ureteral dilatation and double-J ureteral catheters were also inserted. Diagnostic ureteroscopy was successful in all cases. Two complications (one urinary leakage and one symptomatic urinary tract infection) occurred and were managed conservatively.

CONCLUSIONS

Ureteral endoscopy is a safe and effective method for the management of urological complications after renal transplantation. This procedure can be considered the first choice, in preference to percutaneous and antegrade modalities.

Ureteral complications in renal transplant recipients successfully treated with interventional radiology

INTRODUCTION

Ureteral complications in renal transplantation occur in approximately 8% of renal transplant recipients, occasionally leading to graft loss. This retrospective study presents a single-center experience in managing ureteral complications with interventional radiology as well as the long-term graft function and recipient survival.

PATIENTS AND METHODS

We analyzed 21 renal transplant recipients with ureteral problems.

RESULTS

Nine patients experienced urinary leak, six patients had ureteric obstruction, and six patients had obstruction preceded by leak. Median recipient age was 48 (range, 20-63) years; 71% (15/21) of the patients were male and 66.6% (14/21) of transplants were derived from cadaveric donors. Ureteral complications were diagnosed at a mean of 18 days (range, 12-47) after renal transplantation. Initially a percutaneous nephrostomy was performed, followed by antegrade placement of a nephroureteral stent. In cases with ureteral obstruction, ureteral balloon dilation was performed prior to placement of the stent. Median time to the procedure was 53 days, and median follow-up for the purposes of this study was 57 months. Renal graft function improved following treatment of the ureteral complication. Mean serum creatinine values prior to and after the intervention were 4.8 +/- 2.12 and 1.79 +/- 0.58 mg/dL, respectively (P < .0001). Functional renal grafts were observed at the first, third, and fifth posttransplantation year among 100%, 95.2% and 80.9% of patients, respectively. It should be further noted that no graft was lost due to a ureteral complication.

CONCLUSIONS

Interventional radiology was successful in treating immediate and long-term ureteral problems among renal transplant recipients with preservation of good renal function and patient survival.

Endourological Management of Ureteral Stenosis and Vesicoureteral Reflux after Renal Transplantation

Introduction and Objectives

Ureteral stenosis and vesicocoureteral reflux after renal transplantation represent a key concern because of their incidence and the associated morbidity. Prompt diagnosis and minimally invasive treatment are mandatory in immunosuppressed patients with single kidney. The aim of this study is to evaluate the success rate of the endourological techniques in the management of such complications.

Materials and Methods

Between January 1996 and December 2006, 647 kidney transplants were performed. Urinary tract continuity was re-established by ureteroneocystostomy according to Gregoir-Lich technique. We observed 13 cases of ureteral stenosis (2%) and 11 cases of symptomatic vesicoureteric reflux (1.7%). The endourogical procedure was performed in 13 patients: 5 cases of II-III grade vesicoureteric reflux, 4 early ureteral stenosis and 4 late ureteral stenosis. Patients with vesicoureteric reflux underwent endoscopic injection of macroplastique in 4 cases and Durasphere in 1. Early ureteral stenoses were treated using balloon dilation in 2 cases, balloon dilation and laser endoureterotomy in 3, ureteral stent placement in the other. Recipients with late stenosis underwent laser incision and balloon dilation in 2 cases, balloon dilation in 1 and a laser incision only in the last case. Combined antegrade and retrograde endoscopic approach was performed in 7 patients, whereas retrograde access in 1.

Results

Endourologic treatment was successful in 9 cases (69.2%); 2 patients required open reconstructive surgery due to endourological technique failure (early ureteropelvic junction stricture, late ureterovesical anastomotic stricture). Vesicoureteric reflux was corrected in 3 patients (60%), 2 patients underwent uretero-ureterostomy for recurrent reflux. No technique-related morbidity was observed. With a mean follow-up of 81.6 months, 8 patients show normal renal function, 5 patients have returned to haemodialysis (4 for chronic rejection, 1 for carcinoma in the graft).

Conclusions

Considering their low morbidity and the satisfactory success rate, we claim that endourological procedures should be considered the preferred treatment for ureteral stenosis and vesicoureteric reflux in selected patients.

Stent-related ureteric obstruction in paediatric renal transplantation

The rates of ureteric obstruction and complications for use of externally draining uretero-vesico-cutaneous (external) stents (Group 1: n=39) and the use of internal uretero-vesical (double-J) stents (Group 2: n=16), in 55 of 64 consecutive paediatric renal-transplant recipients, performed at our institution between January 1996 and December 2003, have been compared. Serum creatinine levels pre and post-operatively and pre and post-stent removal were recorded. The diagnosis of ureteric obstruction was based on an increase in serum creatinine of >or=20%, in conjunction with ultrasound evidence of hydronephrosis or hydroureter, where other causes of renal dysfunction were excluded. Ureteric obstruction occurred in 13 of the 39 patients (33.3%) in Group 1, compared with only one case of ureteric obstruction in the 16 patients (6.25%) in Group 2 (OR=7.5, 95% CI=0.8-70, P=0.038). There was no evidence of a difference in the number of urinary tract infections (9/39 in Group 1, 6/16 in Group 2, OR=0.5, 95% CI=0.14 to 1.8, P=0.275) or the mean length of hospital stay (10.9 days in Group 1, 10.1 days in Group 2, 95% CI=-2.3 to 4 days, P=0.565) between the two groups. Glomerular filtration rate (GFR) improved in the week after stent removal in Group 2, but deteriorated in Group 1 (P=0.07). This non-randomised comparison of stent types supports the use of prophylactic double-J stents in paediatric renal transplantation- in terms of decreased ureteric complications and improved renal function post-stent removal.

Self-Expanding Metallic Ureteral Stents for Treatment of Ureteral Stenosis After Kidney Transplantation

The incidence of post-renal transplantation ureteral stenosis ranges from 2%-12%. Because the role of self-expanding ureteral metallic stents for its treatment has been scarcely reported, the aim of this study was to evaluate the efficacy of Nitinol stents. Eleven ureteral stenoses in patients with chronic graft dysfunction (8 cases) or high surgical risk (3 cases) were treated by antegrade percutaneous implantation of Nitinol stents through a nephrostomy tract. The mean follow-up period was 48 +/- 7 months (range, 3-85 months). The patency rate at the moment of return to dialysis, death, or last check-up was 73% (8/11). Three patients (27%) developed stent occlusion. Two patients were treated using a trans-stent double-J catheter and 1 patient using stent removal and pyeloureterostomy using the native ureter. The mean percentage decrease in serum creatinine (Cr) level after stent implantation was 41% (range, 14%-63%). Nitinol ureteral stent implantation is an effective alternative for the treatment of ureteral stenosis in patients with chronic graft dysfunction or high surgical risk.

Retrograde stenting for obstruction of the renal transplant ureter

OBJECTIVES

To present our experience with retrograde stent placement and stent exchange for transplant ureteral obstruction.

METHODS

A review of our renal transplant database was performed to identify all renal transplant patients who underwent attempted retrograde ureteral stenting for allograft ureteral obstruction or attempted allograft ureteral stent exchange between May 1992 and April 2004. A retrospective review was performed.

RESULTS

Forty patients underwent 52 attempted retrograde ureteral stent placements, and 11 patients underwent a total of 27 attempted stent exchanges. In patients with ureteral obstruction, the most common clinical signs and symptoms were nausea, vomiting, diarrhea, abdominal pain, fever, decreased urine output, edema, and an elevated serum creatinine. Of the 52 cases of allograft ureteral obstruction and attempted retrograde ureteral stent placement, 28 (53.8%) were managed successfully with retrograde ureteral stenting. Of the 27 attempted stent exchange procedures, a successful exchange was accomplished in 23 cases (85.2%).

CONCLUSIONS

Cystoscopy with retrograde allograft stent placement is a reasonable first approach to the management of transplant ureteral obstruction and is successful in more than one half of cases.

Ureteroscopic endoureterotomy

OBJECTIVE

To highlight the current status of ureteroscopic endoureterotomy (UE) by reporting extensive experience with the endoscopic management of ureteric strictures, with special emphasis on factors determining success, and by reviewing publications on the minimally invasive management of ureteric strictures.

PATIENTS AND METHODS

The study comprised 50 patients (mean age 53 years, range 18-85, equal sex distribution) with ureteric strictures of varying causes; all had their stricture treated endoscopically. The follow-up was 0.5-9 years; 10 patients with recurrent strictures had two ipsilateral stents placed to try to improve the outcome, and eight patients with completely obliterating strictures were treated by ureteroscopic re-canalization.

RESULTS

The site of stricture had no bearing on the eventual outcome. Patients with uretero-enteric and malignant strictures did not fare so well. The most important predictor of failure was the length of the stricture, with failure in all seven patients with strictures of > 2 cm. In the 10 patients treated with two ipsilateral stents, eight were successful, which was very promising considering that these patients had recalcitrant strictures and placing one stent had previously failed. The overall success rate was 74%.

CONCLUSION

UE has become the procedure of choice for the initial management of ureteric strictures. Simple balloon dilatation is also effective in certain situations. The characteristics of the stricture often govern the eventual outcome. In properly selected cases success rates of approximately 75% can be expected.

Prolonged ureteral stenting in obstruction after renal transplantation: long-term results

BACKGROUND

Renal transplantation is an effective treatment for end-stage renal disease. Ureteral stenosis is the most frequent urologic complication. We report our long-term follow-up results concerning endourologic treatment of ureteral obstruction after renal transplantation.

METHODS

Between May 1997 and September 2000, 15 patients with renal transplant obstructive uropathy were managed with percutaneous nephrostomy and prolonged ureteral stenting.

RESULTS

Percutaneous nephrostomies were performed successfully in all 15 kidneys. In 13 patients, antegrade ureteral stenting was attempted, which was successful in 11 patients (85%). After prolonged ureteral stenting (mean duration 15 months), the stent was removed in all patients, 90% of whom had no recurrence. During follow-up (36 to 71 months; mean 51), urea, creatinine, sodium, and potassium determinations and ultrasound scans were performed. Success was defined as a reduction in hydronephrosis. No major complications were observed.

CONCLUSIONS

Modern endourologic procedures have replaced open reconstructive surgery in most patients with ureteral obstruction after renal transplantation, because they may offer a definitive treatment with low morbidity.

Treatment of renal transplant ureterovesical anastomotic strictures using antegrade balloon dilation with or without holmium:YAG laser endoureterotomy

OBJECTIVES

To report our results after antegrade endoscopic treatment of ureteral stenosis with balloon dilation with or without holmium laser endoureterotomy. Ureteral stenosis is the most common long-term urologic complication of renal transplantation.

METHODS

From July 2000 to October 2002, 9 renal transplant patients with ureteral obstruction diagnosed by an increase in serum creatinine and radiologic evidence presented for endoscopic treatment. All patients were treated with nephrostomy tube drainage followed by antegrade flexible nephroureteroscopy and balloon dilation of the stricture. Three patients required holmium laser endoureterotomy during the same procedure because of fluoroscopic and endoscopic evidence of persistent stricture. All patients were treated with ureteral stents and nephrostomy tubes postoperatively. The median follow-up was 24 months (range 6 to 32).

RESULTS

The site of stenosis was at the ureterovesical anastomosis in all patients, and the mean stricture length was 0.28 cm. Two patients had previously undergone ureteroneocystostomy for prior ureteral stenosis. Six patients (66%) required only balloon dilation, and 3 patients (33%) also required holmium laser endoureterotomy. The median ureteral stent and nephrostomy tube duration was 40 and 62 days, respectively. The mean serum creatinine level was 2.3 mg/dL at presentation and 1.7 mg/dL at the last follow-up visit. After a median follow-up of 24 months, the ureteral patency and graft function rates were both 100%. No perioperative complications occurred.

CONCLUSIONS

Balloon dilation with or without holmium laser endoureterotomy was successful and safe in this group of renal transplant patients with short ureterovesical anastomotic strictures.

Transplant ureter stricture: Acucise endoureterotomy and balloon dilation are effective

PATIENTS AND METHODS

Eight patients with ureteral stricture after renal transplantation underwent minimally invasive treatment with Acucise incision or balloon dilation. Acucise endoureterotomy was used to treat four patients with strictures at the ureterovesical anastomosis, and balloon dilation was used to treat four patients with a ureteroureterostomy stricture. Success was defined as an acceptable serum creatinine concentration in the absence of hydronephrosis with at least 1 year of follow-up.

RESULTS

Acucise endoureterotomy for ureterovesical anastomosis stricture was successful in two of three patients (67%) with a mean follow-up of 20 months. One patient had an indeterminate outcome. Balloon dilation of strictured ureteroureterostomy was successful in three of four patients (75%) with a mean follow-up of 23.7 months. Three of the four patients with previously failed open revision were treated successfully with endourologic techniques. The two patients in whom treatment failed had strictures >/=1.5 cm and manifested comorbidities including diabetes mellitus.

CONCLUSION

As our results are comparable to those of other published series, endourologic management of transplant ureteral stenosis is a reasonable strategy.

Obstructive uropathy in the transplanted kidney: definitive management with percutaneous nephrostomy and prolonged ureteral stenting

BACKGROUND AND PURPOSE

Renal transplantation is an effective treatment for end-stage renal disease. Ureteral stenosis is the most frequent urologic complication. We report our experience with percutaneous nephrostomy and antegrade ureteral stenting, which may offer a primary and definitive alternative to open surgery.

PATIENTS AND METHODS

Fifteen patients with renal allograft obstructive uropathy were managed with percutaneous nephrostomy and prolonged ureteral stenting.

RESULTS

Percutaneous nephrostomies were successfully performed in all 15 kidneys: In 13 patients, antegrade ureteral stenting was attempted, this being successful in 11 (85%). After prolonged ureteral stenting (mean duration 15 months), the stent was removed in eight patients, and six of them (75%) did not have recurrences. During follow-up, urea, creatinine, sodium, and potassium determinations and ultrasound scans were performed, and success was confirmed by the decline of creatinine and reduction in hydronephrosis. No major complication was observed.

CONCLUSION

Percutaneous nephrostomy and ureteral stenting is a safe and effective treatment for renal allograft obstructive uropathy. Prolonged ureteral stenting may offer a definitive treatment with low morbidity.

Renal transplant complications. Minimally invasive management

Advancements in endourology, laparoscopic urology, and interventional radiology continue to influence the contemporary management of renal transplant complications. The successful implementation of these minimally invasive therapies significantly relies on careful patient selection; not all renal transplantation complications are suitable or amenable for this form of management--true for transplant ureteral complications and less so for other potential complications. With such a strategy, renal transplant complications can be managed efficiently and effectively with these minimally invasive modalities to minimize further recipient morbidity while also minimizing potential risk to the recipient and for the renal allograft.

Management of ureteral strictures in renal transplants by antegrade balloon dilatation and temporary internal stenting

PURPOSE

To evaluate the efficacy of percutaneous balloon dilatation and temporary internal stenting in the treatment of transplant ureteral strictures.

METHODS

Nine patients presenting with obstructed renal transplants were treated by antegrade nephrostomy insertion, ureteroplasty, and temporary internal stenting. Following stent removal, patients were divided into two groups for analysis according to whether the obstruction occurred less than (group A) or more than (group B) 3 months following transplantation.

RESULTS

All procedures were technically successful. In group A (n = 6), all patients were successfully treated by one or two dilatations with stenting. In group B (n = 3), two patients were successfully treated by one dilatation with stenting. Overall, eight patients (89%) have had their primary or secondary stent removed successfully at a mean interval of 97.5 days after insertion, and remain well at a mean follow-up interval of 22 months.

CONCLUSION

Balloon dilatation and temporary internal stenting is a useful method for treating transplant ureteral strictures.

Results of pyeloureterostomy after ureterovesical anastomosis complications in renal transplantation

OBJECTIVES

The most frequent urologic complications after renal transplantation involve the ureterovesical anastomosis (ie, leakage, stenosis, and reflux), with a frequency of 1% to 30% in different series. We present the results of pyeloureterostomy using the recipient's ureter.

METHODS

From 1988 to 1996, 570 cadaveric renal grafts were performed at our institution. A Lich Gregoir ureterovesical anastomosis was used in every case. Complications involving the anastomosis occurred in 19 cases (3.3%), with 10 stenoses (1.7%), 6 cases of leakage (1.1%), and 3 of reflux (0.5%). The mean donor age was 36.2 years, and the mean duration of cold ischemia was 29.4 hours. The mean recipient age was 41.3 years. Corrective surgery was performed 0.09 years (range 0.01 to 0.22) after transplantation for leakage, 1.13 years (range 0.14 to 5.11) for stenosis, and 5.55 years (range 0.51 to 9.71) for reflux. The recipient's ureter was stented with a ureteral catheter before median laparotomy, except in 3 cases of early leakage (less than 3 days). The recipient's ureter was cut, without the need for ipsilateral nephrectomy, and sutured to the graft pelvis. A nephroureterostomia stent (Gil Vernet stent) (12 cases) or a double J ureteral stent (7 cases) was used for urinary drainage.

RESULTS

One graft was lost on day 1 through renal vein thrombosis. Percutaneous nephrostomy was performed on day 2 to clear an obstruction of the double J ureteral stent in one case, and a double J ureteral stent was inserted on day 2 because the nephrouretrostomia stent was incorrectly positioned in another case. Pyelographic controls on day 15 were normal in every case. The mean follow-up was 2.25 years (range 0.24 to 6.1) (2.9 years for leakage, 2.08 years for stenosis, and 1.44 years for reflux). One patient died with a functional graft 3 years after surgery. One graft was lost 4 years after surgery through chronic rejection. There were no complications affecting the ipsilateral kidney. No further ureteral complications occurred after surgery. The mean creatinine level 3 years after surgery was 1.59 mg/dL.

CONCLUSIONS

Pyeloureterostomy is a safe and permanent treatment for complications of ureterovesical anastomosis and gives excellent results. The technique requires stenting of the recipient's ureter and graft drainage with a nephroureterostomia stent or a double J ureteral stent.

Update on interventional uroradiology

From its humble beginnings as a method of expediently decompressing the obstructed kidney, the field of interventional uroradiology has evolved in the hands of urologists and interventional radiologists to a means of addressing myriad problems in the urinary tract and has changed the day-to-day practice of urology. The foundation of interventional uroradiology is the creation of an appropriate entry into the urinary system. After a review of this basic procedure, extensions of the technique and new applications of emerging technology are reviewed.