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

Single-port robotic-assisted ureteral reconstruction for management of strictures after renal transplantation

Ureteral strictures are a common and often challenging complication of renal transplantation. The use of single-port (SP) robotic-assisted laparoscopic surgery is a novel approach in the management of these patients. Here we describe 3 patients with stricture of the transplant ureter causing hydronephrosis and allograft dysfunction, whose ureteral reconstructions were successfully performed using the SP robotic-assisted laparoscopic approach. Two patients underwent transplant-to-native ureteroureterostomy and 1 patient underwent ureteroneocystostomy. We demonstrate that the use of concurrent ureteroscopy and near-infrared fluorescence enables safe and rapid identification of native and transplant ureters. In addition, side-to-side anastomosis of transplant-to-native ureters allows for preservation of ureteral vasculature. In this limited series, the SP robotic platform demonstrates great promise in simplifying and streamlining our approach to ureteral strictures in this patient population.

Ureteral Stenosis and Fistula after Kidney Transplantation

INTRODUCTION

Ureteral complications after kidney transplantation are frequent and may have a negative impact on morbidity and graft function. Treatment modalities include conservative, endourological, and surgical techniques, with variable outcomes. The purpose of this study was to report the incidence, characteristics, treatment, and outcomes of ureteral complications at our center.

METHODS

Retrospective study of kidney transplants performed at our unit between 2015 and 2020, analyzing incidence, characteristics, treatment, and outcomes of ureteral stenoses and fistulas.

RESULTS

Of 648 kidney transplants, we present 3.24% stenosis and 2.16% ureteral fistulas, with a mean time from transplantation of 101.4 and 24.4 days, respectively. Primary treatment was open surgical repair in 52.4% stenosis and 100% fistulas, with a success rate of 90.9% and 71.4%, respectively. Anterograde balloon dilatations were performed in 33.3% of stenosis with 40% success. Three patients required surgery as a secondary approach with 100% success. Major complications (Clavien-Dindo III) were observed in 18.5% following surgical repair. After a mean follow-up of 31.1 ± 20.9 months, we observe 88.6% of functioning grafts. We found no significant differences in graft survival between patients with or without ureteral complications (p 0.948).

CONCLUSION

Surgical repair of ureteral complications offers satisfactory results with low associated morbidity. Endourological techniques are less effective and should be reserved for selected cases. With adequate management, there is no impact on graft survival.

Does STING failure affect short-term graft functions in renal transplant patients: a single-center study

PURPOSE

The aim of the present study was to evaluate outcomes of symptomatic VUR treatment in transplant patients, compare open and endoscopic approaches in terms of graft functions, success rates, complications and recurrent UTIs.

METHODS

67 patients who undergone only STING and STING followed redo UNC due to symptomatic VUR after kidney transplantation were included into the investigation. Patients who had lower urinary tract dysfunctions were excluded from the trial. For 67 patients, baseline and before final surgery and 3rd month creatinine and GFR levels were recorded. Twenty-six of those 67 patients had redo UNC due to failed STING. The data of those patients were compared with the remaining 41 patients who had only STING.

RESULTS

In both groups no statistically significant variations in serum creatinine and GFR levels were detected during follow-up (p > 0.05). Serum levels after STING and in the 3rd month of redo UNC were compared. Although variation was observed in serum creatinine levels and in GFR levels, was not statistically significant (p: 0.59 and p: 0.23). The success rate of STING was %61.1 in 67 patients, and was not significantly different when three VUR grade groups (Grade 3 n:17, Grade 4 n:24, Grade 5 n:36) were compared (p > 0.05).

CONCLUSION

The present study revealed that subureteral endoscopic injection is cost effective and safe for the first-line treatment due to its minimally invasive nature, does not cause delay which leads to deterioration of graft functions. Redo-UNC has acceptable morbidity and complication rates, should be considered when STING is failed.

Long-term results of endoscopic treatment in vesicoureteral reflux after kidney transplantation

OBJECTIVES

To assess the long-term clinical outcomes and identify factors predicting success of endoscopic treatment for symptomatic vesicoureteral reflux (VUR) after kidney transplantation.

PATIENTS AND METHODS

A retrospective chart review of all patients who had a symptomatic VUR after renal transplantation at our centre between January 2000 and December 2020 was performed. VUR was documented by retrograde cystography and was determined by at least one episode of acute graft pyelonephritis (AGPN). Endoscopic injections of polydimethylsiloxane (MacroPlastique^™) or dextranomer/hyaluronic acid copolymer (Deflux^™) were performed by expert urologists via rigid cystoscopy with a bevelled needle system. The results of endoscopic treatment were evaluated by cystography at three months. The primary endpoint was clinical efficacy as defined by the absence of AGPN during follow-up. Radiological success was defined by the absence of VUR at the three months follow-up cystography.

RESULTS

Out of 2135 kidney transplantations, a total of 117 (5.5%) patients had symptomatic VUR: 100 (85.5%) underwent Deflux^™ and 17 (14.5%) MacroPlastique^™. Preoperative high-grade VUR was recorded in 71% of patients. One postoperative complication was observed, Clavien > II. After a median follow-up of 11.2 years (IQR 6.5-14.4), clinical success was achieved in 73 patients (62.4%). Radiological success was obtained in 42 patients (36%). Multivariable analysis failed to identify predictors of endoscopic treatment success, which was independent of the preoperative grade of VUR and the type of bulking agent used.

CONCLUSION

Endoscopic treatment of VUR is a simple and well-tolerated procedure with long-term clinical efficacy.

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.

Treatment of Vesicoureteral Reflux Detected After Renal Transplant in Pediatric Patients: A Single-Center Experience

OBJECTIVE

In children who undergo renal transplant, vesicoureteral reflux on the transplanted kidney is a serious complication that may result in organ loss. In this study, we aimed to evaluate the results of endoscopic and open surgical techniques in the treatment of patients with recurrent urinary tract infections and vesicoureteral reflux after renal transplant.

MATERIAL AND METHODS

The files of pediatric patients who underwent renal transplant in our hospital between January 2016 and January 2019 were evaluated retrospectively. In this single-center analysis, we investigated the incidence of vesicoureteral reflux in the kidney transplant recipients and the results of various approaches to treat it.

RESULTS

Eighty pediatric patients underwent renal transplant between January 2016 and January 2019. Fourteen of those patients (17.5%, 7 female and 7 male) were diagnosed with vesicoureteral reflux in the postoperative period. Twelve of 14 patients received endoscopic injections as the first treatment. Clinical or radiological success was achieved in 5 patients (5 of 15 injection treatments, 33%); in 4 patients (4/12, 33.3%) success was after the first endoscopic injection treatment, and in 1 patient (1/3, 33.3%) success was after the second injection. Meanwhile, clinical or radiological success was achieved in 6 of 7 patients who underwent redo ureteroneocystostomy (6/7, 85.7%).

CONCLUSION

Although symptomatic vesicoureteral reflux after renal transplant is rare in pediatric patients, it is an important cause of morbidity as it requires recurrent surgical procedures. Although endoscopic treatment is safe and minimally invasive, the success rate is lower than expected, and redo of ureteral reimplant may be required in most cases.

Perfect outcome of kidney recipients with ureteral stenosis after treatment with open surgery under magnetic resonance urography localization

Background

To evaluate the outcome of kidney recipients with ureteral stenosis after treatment with open surgery under magnetic resonance urography (MRU) localization.

Methods

We assessed 2,256 consecutive kidney transplant recipients between October 2010 and December 2018. Ureteral stenosis was detected by ultrasound, confirmed and positioned by Magnetic Resonance Urography. All patients underwent open ureteral reconstruction. The ureteral stenosis was located according to the location on the MRU during the operation. Surgical complications and recurrence rate were recorded in the stenosis group. Outcomes were compared with those of a matched control group of transplant recipients with no history of ureteric stenosis.

Results

The incidence of ureteral stenosis in our center was 3.1% (70/2,256). Sixty-four cases (91.4%) were confirmed to have distal stenosis and were reconstructed with ureterovesical re-implantation; six cases (8.6%) were confirmed to have mid-distal stenosis and were subjected to ureteroureterostomy with the use of native ureter. The overall success rate was 100% and the graft function was salvaged in all cases. There was no recurrence of stenosis after a mean follow-up of 38.9±26.3 months. The complication rate was 5.7%. The 110-month graft survival and patient survival were not significantly different between the stenosis and control groups.Conclusions: MRU is an effective method for non-invasive and accurate diagnosis of ureteral stenosis in kidney transplant recipients. Open ureteral reconstruction surgery under MRU localization for treatment of ureter stenosis after kidney transplantation had a high success rate, low recurrence rate and high safety.

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.

The Efficiency and Safety of Endoscopic Treatment on Kidney-Transplanted Patients With Symptomatic Vesicoureteral Reflux in Native and Transplanted Renal Units

OBJECTIVES

To evaluate the outcome of endoscopic treatment of symptomatic vesicoureteral reflux (VUR) in patients with VUR in both transplanted and native renal units.

MATERIAL AND METHODS

Between January 2014 and December 2019, 23 transplanted patients with symptomatic VUR with reflux in both transplanted and native kidney were included in the study. All patients were patients with a history of kidney failure due to reflux nephropathy. A voiding cystourethrography was performed after at least 1 episode of acute glomerulo pyelonephritis or deterioration of the graft function. All patients underwent a urine culture and an ultrasonic evaluation preoperatively. A dextranomer/hyaluronic acid bulking agent was injected via endoscope by a rigid metal needle around a double J stent. Clinical success was defined as absent of febrile urinary tract infection during the follow-up period.

RESULTS

The procedure was applied in 52 effected renal units; of these, 27 were transplanted kidneys, and 25 were native kidneys. Overall clinical success was achieved in 69.6% (N = 16) of patients. The success rate after the first procedure was 52.2% (N = 12), whereas 17.3% (N = 4) achieved success after the second treatment. No intraoperative complications occurred throughout the endoscopic procedure. Minor postoperative complications included 2 (10%) cases of self-limiting episodes of hematuria that did not require intervention.

CONCLUSION

Endoscopic treatment of symptomatic VUR for both transplanted ureter and native ureter is a safe treatment in most of the patients. Therefore, endoscopic ureteral injection is a treatment modality with low morbidity that should be preferred to open surgery as first-line treatment in this subgroup of patients.

Early Complications After Kidney Transplantation in Patients Aged 60 Years and Older: A Single-Center, Paired-Kidney Analysis

OBJECTIVES

As the population ages, the number of people suffering from cardiovascular diseases (CVD) and diabetes mellitus (DM) increases. The coexistence of these diseases can affect the results of kidney transplantation (KT) in the elderly. The aim of this study was to analyze surgical and nonsurgical complications in the early period after KT and to identify the factors that influence their development in recipients aged ≥ 60 years compared to younger recipients < 60 years.

METHODS

One hundred seventy-five recipients of KT ≥ 60 years and 175 recipients of KT < 60 years who received kidneys from the same deceased donor were enrolled into the study. The incidence of surgical and nonsurgical complications, factors that may influence their development, early graft function, and patient and kidney-graft survival were analyzed during a 3-month follow-up period. Donor sources complied with the Helsinki Congress and Istanbul Declaration and organs were not procured from prisoners and individuals who were coerced or paid.

RESULTS

Older recipients were characterized by higher body mass index ± SD (26.1 ± 3.5 vs 24.7 ± 3.4 kg/m²) and suffered more often from pretransplant DM (20.6% vs 11.4%) and CVD (34.3% vs 10.3%) and less frequently underwent previous KT (6.3% vs 20.0%). There were no differences between the ≥ 60 year old and < 60 year old groups in reference to surgical (20.6% vs 24%) and nonsurgical complications (28.6% vs 27.4%), early graft function, serum creatinine, and proteinuria. Recipients (95.4% vs 97.1%) and kidney-graft survival (93.1% vs 95.4%) were similar in both groups. The recipient factors that influenced the development of infectious complications were age, dialysis duration, pretransplant DM, and CVD.

CONCLUSIONS

Despite higher co-incidence of CVD and DM, the risk of surgical and nonsurgical complications in elderly recipients is comparable to younger recipients in the early period after KT.

Endoscopic treatment of symptomatic VUR disease after the renal transplantation: analysis of 49 cases

BACKGROUND

To evaluate the outcome of endoscopic treatment for symptomatic vesicoureteral reflux (VUR) disease in renal transplantation patients and to determine the factors that were associated with the success rate of the treatment.

METHODS

A total of 121 symptomatic VUR diseases diagnosed between 2014 and 2018 in 3560 renal transplant patients. The results of 49 VUR cases that presented with febrile urinary tract infection (UTI) and were hospitalized for antibiotic treatment were included in the study. Reflux was detected by voiding cystourethrogram and treatment was performed by endoscopic Deflux® injection. The result of endoscopic treatment was evaluated clinically by 3 months periods.

RESULTS

The mean time between transplantation and endoscopic treatment was 59.6 (5-132) months, and the mean follow-up period after the endoscopic treatment was 14 (6-48) months, respectively. The success rate after the first injection was 59.1% (n = 29) and 67.3% (n = 33) after the second injection. One patient developed anuria, one patient febrile UTI and four patients developed minimal macroscopic hematuria after the procedure.

CONCLUSIONS

Endoscopic treatment of symptomatic VUR in transplanted kidney is a safe and feasible procedure. The amount of bulking agent or duration between the transplantation and diagnosis of VUR does not have any impact on the success of the treatment. However, the younger age of the patients and the female gender seem to have a positive effect on the outcome of the procedure.

Efficiency and Safety of the Sting Operation on Kidney Transplanted Patients with Symptomatic Vesicoureteral Reflux and Neurogenic Bladder Dysfunction

PURPOSE

The study aimed to evaluate the feasibility and effectiveness of the endoscopic treatment in transplanted patients with neurogenic bladder who complained of symptomatic vesicoureteral reflux (VUR).

MATERIAL AND METHODS

Fifteen patients with VUR who were previously diagnosed with a neurogenic bladder were included in the study. The Lich-Gregoire technique was used for ureterovesical anastomosis during transplantation, and a double J stent was inserted routinely in the ureter to protect the anastomosis. The sting operation was performed under general anesthesia in the lithotomy position. A 4.8 Fr double J stent (Boston Scientific, Boston, MA) was inserted to prevent the risk of ureteral obstruction. Successful treatment was defined as absent acute glomerulopyelonephritis (AGPN) during follow-up and as absent VUR on radiological evaluation.

RESULTS

Clinical success was achieved in 6 of 10 patients (60%) who presented with recurrent febrile urinary tract infection (UTI) and in 4 of 6 (66%) patients who presented with gradually graft function deterioration. In 3 patients, the ureteral neo-orifice could not be localized during the operation owing to severe trabeculation of the bladder wall. The other 2 patients with a previous history of augmented bladder procedures had a hypotension attack during bladder filling; hence, the operation was stopped to prevent further complications. Two patients, whose clinical symptoms did not resolve after the sting procedure, accepted open ureteral reimplantation surgery.

CONCLUSION

Endoscopic management of the VUR in the transplant patients with neurogenic bladder function is safe and effective in at least half of the patients in a mid-term follow-up period.

Endoscopic Treatment for Post-Transplant Vesicoureteral Reflux

INTRODUCTION

Vesicoureteral reflux (VUR) is one of the most common ureteric complications after kidney transplantation that might cause symptomatic infections which deteriorate graft function. Surgical reimplantation has been the standard treatment; recently, endoscopic injection has been an alternative approach. We report our endoscopic treatment results and analyze the long-term outcome, even in patients with less optimal graft function.

MATERIALS AND METHODS

A total of 16 patients and 19 symptomatic VUR were diagnosed at mean time of 88.3 months after their transplantation. The distribution of VUR grade was 1, 2, 8, 6, and 2 for grade I to V, respectively, with a mean VUR grade of 3.26 according to their voiding cystourethrogram images. Endoscopic Deflux injections were performed by a single urologist via rigid cystoscope with a beveled needle system. They were followed monthly thereafter.

RESULT

The average number of admissions due to symptomatic urinary tract infection was 2.68/person, and the mean creatinine level before endoscopic treatment was 1.63 mg/dL. The amount of Deflux injection was 0.7 to 1.2 mL per affected ureter; the mean creatinine level after endoscopic treatment was 1.41 mg/dL. The eGFR remained stationary in both eGFR > 60 and eGFR < 60 mL/min groups with a clinical success rate of 75% in both groups.

CONCLUSION

Endoscopic dextranomer-hyaluronic acid injection is a safe and feasible treatment option for VUR after kidney transplantation. Our data showed its efficacy in recipients whose eGFR is less than 60 mL/min.

Urologic complications in renal transplants

Urologic complications of renal transplant occur commonly and can have significant impact on graft function, survival, and patient morbidity. This review examines the prevalence of urologic complications, risk factors, diagnosis and options for management of the most common urologic complications.

Comparing treatment modalities for transplant kidney vesicoureteral reflux in the pediatric population

INTRODUCTION

Non-refluxing ureteral reimplantation is favored in pediatric renal transplantation to prevent complications, such as vesicoureteral reflux (VUR) in the transplant ureter. VUR resulting in febrile urinary tract infections remains a problem in this population, leading to repeated hospitalizations and increased morbidity. Revision of the vesicoureteral anastomosis can be a surgical challenge due to scar tissue and tenuous vascularity of the transplant ureter. Therefore, alternative options such as endoscopic injection of Deflux at the neo-orifice and surveillance with prophylactic antibiotics have emerged as potential treatment modalities for transplant ureter VUR.

OBJECTIVE

The authors reviewed their experience of the management of VUR in the transplant ureter, comparing outcomes of various modalities.

STUDY DESIGN

With Institutional Review Board approval, a retrospective chart review of all renal transplant patients from January 2002 to January 2017 was conducted. All patients with VUR on voiding cystourethrogram (VCUG) after surgery were identified. Indications for end-stage renal disease, urologic comorbidities, pretransplant VCUG, and operative details were recorded. After transplantation, febrile urinary tract infections, ultrasound findings, and any further interventions-surveillance, subureteral endoscopic injection of Deflux, or ureteral reimplantation-were documented along with their outcomes.

RESULTS

Overall, VUR was identified in 35/285 (12.3%) transplant patients after a non-refluxing ureteroneocystostomy. VUR was managed with surveillance in 17/35 (49%), intravesical Deflux injection in 11/35 (31%), and immediate redo ureteral reimplantation in 7/35 (20%). Ten out of 11 patients undergoing Deflux injection had a postoperative VCUG. All patients developed VUR recurrence; the majority showed immediate failure and only 1/10 showed late recurrence. Of the immediate failures, 3/9 patients were maintained on prophylactic antibiotics, and 6/9 patients underwent ureteral reimplantation. In these six patients undergoing reimplantation after failed Deflux, 3/6 (50%) patients required additional surgeries: One patient developed recurrence of reflux and two patients developed ureterovesical junction obstruction. In contrast, no complications were seen in patients undergoing primary ureteral reimplantation.

DISCUSSION

The study is limited by low numbers and a retrospective design. However, the results of this study differ significantly from the published Deflux series showing a success rate of more than 50% in the treatment of transplant kidney VUR. In fact, post-Deflux redo ureteral reimplantation was associated with an increased risk of postoperative complication.

CONCLUSION

The use of Deflux in the post-transplant setting has poor results. In the study series, 11/11 patients demonstrated clinical and radiographic failure. Therefore, as an institution the authors do not recommend Deflux as first-line treatment of VUR in the transplant patient.

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.