Deflux Injections for Vesicoureteral Reflux in Transplanted Kidneys

Children Are Not Small Adults: Similarities and Differences in Renal Transplantation Between Adults and Pediatrics

Kidney transplantation is the treatment of choice for all patients with end-stage kidney disease, including pediatric patients. Graft survival in pediatrics was lagging behind adults, but now is comparable with the adult cohort. Although many of the protocols have been adopted from adults, there are issues unique to pediatrics that one should be aware of to take care of this population. These issues include recipient size consideration, increased incidence of viral infections, problems related to growth, common occurrence of underlying urological issues, and psychosocial issues. This article addresses the similarities and differences in renal transplantation, from preparing a patient for transplant, the transplant process, to post-transplant complications.

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.

Revision ureteroneocystostomy in pediatric renal transplant patients for symptomatic vesicoureteral reflux and its effect on recurrent hospitalizations

BACKGROUND

Nearly 13,000 pediatric renal transplantations have been performed since 1987 with improving overall mortality and morbidity; however, graft infection remains a significant post-transplant concern. Recurrent urinary tract infections in pediatric patients with vesicoureteral reflux into their renal transplant can result in graft dysfunction, increased hospital cost, and impaired social and cognitive development due to time spent hospitalized.

OBJECTIVE

To evaluate the effect of revision ureteroneocystostomy on pediatric renal transplant patients with symptomatic vesicoureteral reflux in reducing hospitalizations and recurrent urinary tract infections.

METHODS

We retrospectively reviewed pediatric patients from 2002 through 2021 who underwent renal transplantation and required revision ureteroneocystostomy due to symptomatic vesicoureteral reflux. We analyzed the differences in days hospitalized, days hospitalized due to urinary tract infection, and treated urinary tract infections prior to and after revision ureteroneocystostomy.

RESULTS

Ten patients requiring revision ureteroneocystostomy secondary to symptomatic vesicoureteral reflux were identified. There was no difference in the observation time between transplant to revision, and revision to last follow up (2.3 years (IQR 1.3-6.5) vs 1.7 years (IQR 1-6.7), p = 0.4446). Overall, there was a significant decrease in the total number of hospitalization days (21.5 days (IQR 3-43) vs 5.5 days (IQR 0-9), p = 0.006), total number of hospitalization days related to urinary tract infection (14.5 days (IQR 3-28) vs 0 days (IQR 0-3), p = 0.008) and treated urinary tract infections (3.5 (IQR 3-6) vs 1 (IQR 0-2), p = 0.019) following revision ureteroneocystostomy. The rate of hospitalization days for urinary tract infection was also significantly decreased following revision ureteroneocystostomy (7.15 per/year (IQR 0.4-11.75) vs 0 per/year (IQR 0-0.8), p = 0.008).

DISCUSSION

Symptomatic vesicoureteral reflux in pediatric transplant patients is difficult to manage and some patients will ultimately require surgery. There have been previous studies on the success of revision ureteroneocystostomy in treating reflux but no data on the reduction in hospitalizations associated with recurrent infections following the procedure. Limitations of this study are the small cohort size, retrospective nature, multi-surgeon study, and inherent selection bias due to evaluation of only surgical patients.

CONCLUSION

Revision ureteroneocystostomy can limit the negative consequences of recurrent graft infections with reduction in hospitalization days and improved hospitalization rates due to urinary tract infections. The reduction in hospitalizations can greatly improve the cost of care along with quality of life for transplant patients and should be strongly considered in children with symptomatic vesicoureteral reflux who have failed conservative therapy.

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.

A systematic review of outcomes of Deflux® treatment for vesicoureteral reflux following pediatric renal transplantation

INTRODUCTION

Vesicoureteral reflux (VUR) after renal transplant in the pediatric population may be associated with an increased incidence of urinary tract infection (UTIs) leading to increased morbidity, including graft dysfunction and graft loss. The non-orthotopic location of the transplanted ureter, and lack of submucosal tunnel may pose challenges in correcting the VUR using endoscopic injection techniques. Herein we report the results of a systematic review evaluating the outcomes of endoscopic treatment of VUR using Deflux® in this population.

METHODS

Pubmed and Embase databases were searched from October 2001 to April 2019. Full-text English articles involving patients less than 18 years old at the time of transplant, with a diagnosis of VUR post-transplantation, who underwent Deflux® treatment were included. Figure 1 outlines our PRISMA-compliant search strategy.

RESULTS

We found 6 eligible studies describing Deflux® treatment outcomes in 67 pediatric patients with post-transplant VUR where voiding cystourethrogram (VCUG) confirmed the diagnosis and resolution of VUR. The mean success rate was 36.8%. Ureteral obstruction occurred in 7/67 cases (10.4%). In all these 7 cases of obstruction, ureteric stenting was the initial management, but was only successful in 1 patient. Open ureteroneocystostomy (UNC) was performed in 4/7 cases, while 2/7 were managed expectantly (unknown outcomes). Persistent VUR with UTI despite Deflux® were reported in 20 out of 67 cases. Of these, 7 were managed with prophylactic antibiotics, and 13 with UNC. Success rates were consistently low for UNC after failed Deflux® in comparison to redo UNC in transplant ureters without prior injection.

CONCLUSION

Low success rates are seen following injection techniques for VUR after pediatric renal transplant. Although an appealing option, Deflux® may prove counterintuitive due to the high rate of obstruction and suboptimal results if open reimplantation is required. A multi-institutional prospective study with a larger population size may further elucidate these results.

Management of Vesicoureteral Reflux: What Have We Learned Over the Last 20 Years?

Vesicoureteral reflux (VUR) is associated with increased risks of urinary tract infection, renal scarring and reflux nephropathy. We review advancements over the last two decades in our understanding and management of VUR. Over time, the condition may resolve spontaneously but it can persist for many years and bladder/bowel dysfunction is often involved. Some factors that increase the likelihood of persistence (e.g., high grade) also increase the risk of renal scarring. Voiding cystourethrography (VCUG) is generally considered the definitive method for diagnosing VUR, and helpful in determining the need for treatment. However, this procedure causes distress and radiation exposure. Therefore, strategies to reduce clinicians' reliance upon VCUG (e.g., after a VUR treatment procedure) have been developed. There are several options for managing patients with VUR. Observation is suitable only for patients at low risk of renal injury. Antibiotic prophylaxis can reduce the incidence of UTIs, but drawbacks such as antibiotic resistance and incomplete adherence mean that this option is not viable for long-term use. Long-term studies of endoscopic injection have helped us understand factors influencing use and the effectiveness of this procedure. Ureteral reimplantation is still performed commonly, and robot-assisted laparoscopic methods are gaining popularity. Over the last 20 years, there has been a shift toward more conservative management of VUR with an individualized, risk-based approach. For continued treatment improvement, better identification of children at risk of renal scarring, robust evidence regarding the available interventions, and an improved VUR grading system are needed.

Vesicoureteral Reflux in Adults with Urinary Tract Infections: Is There a Role for Treatment?

PURPOSE OF REVIEW

Urinary tract infections (UTI) place a significant burden on individual patients and the healthcare system as a whole. Vesicoureteral reflux (VUR) is a risk factor for UTIs and is the focus of much research in the pediatric field due to the opportunity for early intervention and prevention of long-term sequelae. However, VUR in the adult population is not well studied and can present different treatment challenges. The goal of this review article is to discuss the role VUR plays in UTIs in the adult population with a specific focus on complications and treatment.

RECENT FINDINGS

The true prevalence of VUR in the adult population remains unknown, and urologists need to maintain an index of suspicion for VUR when evaluating adult patients with recurrent pyelonephritis or complicated UTIs. A number of case series and smaller retrospective studies have documented successful endoscopic treatment of adult VUR patients with recurrent pyelonephritis. Ureteral reimplantation remains an option for adult patients who are refractory to endoscopic treatment of VUR. The current treatments and recommendations for VUR in adults have been extrapolated from the pediatric population due to the scarcity of research. VUR is uncommon in the adult population and requires a high index of suspicion by the clinician. Accurate diagnosis and treatment of VUR can relieve patients from recurrent infections, repetitive antibiotic use, and the risk of hospitalization.

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.

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.

Endourological application of polydimetilsiloxane in patients with symptomatic vesicoureteral reflux in the kidney graft

OBJECTIVE

To identify the results of polydimethylsiloxane application in the endourological management of symptomatic vesicoureteral reflux to the kidney graft and to determine the factors associated with persistent symptoms and with vesicoureteral reflux.

MATERIAL AND METHODS

We included 23 patients diagnosed with symptomatic VUR in kidney graft, evaluated from January 2010 to August 2018 in the High Specialty Medical Unit # 14 in Veracruz. These patients received endourological application of polydimethylsiloxane. The descriptive analysis was carried out, and, if possible, the relative risk measures for clinical failure (CF) were determined with odds ratio (OR).

RESULTS

18 (78.3%) patients presented clinical success (CS). There was a significant difference in the mean age (CS 30.61±9.7, CF 46.0±11.46; U Mann Whitney, P=.037), and in the number of episodes of AGPN prior to the application of PDMS (CS 2.27±1.27, CF 3.6±0.89, U Mann Whitney, P=.019). The most frequently identified pathogen was E. Coli, with 45.4%. VUR resolution was observed in 47.8% of the cases. There was a decreased degree of VUR in 73.9% of cases. A lower degree of VUR was determined as a protective factor for CF (OR: 0.031, 95% CI: 0.002-0.437, with P=.008).

CONCLUSIONS

The endourological application of PDMS proved to be useful in the management of patients with symptomatic VUR in kidney graft, as it decreased the VUR degree and allowed CS in most cases.

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.

Endoscopic Treatment for Vesicoureteral Reflux in Recurrent Urinary Tract Infections in Kidney Transplant: Experience of One Center

Vesicoureteral reflux (VUR) after renal transplantation in adult patients has been reported. In renal transplant recipients, symptomatic urinary tract infection can cause high morbidity despite improved immunosuppressive and antibiotic treatment. In our country there have been few reported cases about use of copolymer of dextranomer and hyaluronic acid (DX-HA) injection in a renal transplant. We present 3 cases of recurrent or complicated infections with evidence of high-grade VUR, which were treated with DX-HA. Only 1 case had a partial remission; however, there were no episodes of urinary tract infection in 12 months of follow-up. Suburethral injection is an endoscopic treatment modality with low morbidity in our country.

Endoscopic antireflux surgery leading to obstruction in pediatric renal transplant patients

To describe a multicenter experience with management of ureteral obstruction after injection of Dx/HA for VUR in pediatric renal transplant patients. The records of all pediatric renal transplant patients who underwent Dx/HA injection for VUR and had subsequent obstruction were identified, and the management and outcomes were reviewed. Follow-up ranged from 1 to 10 years. There were four patients identified, all of whom had a history of rising creatinine, recurrent UTI, and increasing hydronephrosis which led to the diagnosis of high-grade VUR. Obstruction was diagnosed within 24-72 hours after injection in three patients. One patient was asymptomatic, and rising creatinine and hydronephrosis were noted 1 month after injection. One patient was managed expectantly, while three patients underwent ureteral stent placement. After the stent was removed, one patient went on to open reimplant due to delayed obstruction, the second patient with voiding dysfunction is currently managed with an indwelling ureteral stent and may require further definitive surgery, the third patient recovered, and the fourth is being observed. Our cases illustrate that despite initial successful management of the obstruction in some, delayed obstruction is possible and may necessitate open reimplant. It is imperative that these patients have close follow-up after Dx/HA.

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.

Ureteral obstruction following injection of dextranomer/hyaluronic acid copolymer: an infrequent but relevant complication

PURPOSE

To report our experience with ureteral obstruction after injection of dextranomer/hyaluronic acid copolymer (Dx/Ha) to treat vesicoureteral reflux, and analyze its possible causes, management and outcome.

MATERIALS AND METHODS

Retrospective review of patients undergoing injection of Dx/Ha. The charts of patients with clinically relevant ureteral obstruction were evaluated for indications, prior interventions, technique of injection and volume injected. Video recordings obtained during injection were analyzed to detect possible technical errors.

RESULTS

Fifty-four patients (87 ureters) were treated with Dx/Ha injection in a 5-year period. Five ureters (5.7%) in five patients (9.3%) developed significant ureteral obstruction requiring intervention. Manifestations of obstruction included pain in two patients, urinary tract infections in one and loss of function in one. Increased serum creatinine was observed in a patient with a transplanted kidney. Four obstructions resolved spontaneously (two after percutaneous nephrostomy, two after placement of a ureteral stent) and one required reimplantation. Review of the videos did not reveal any deviation from the usual technique. The volumes injected in the obstructed cases (0.7-1.2 ml) were in the usual range.

CONCLUSIONS

In this series, the incidence of post Dx/Ha ureteral obstruction was higher than previously reported. Although 4/5 cases resolved spontaneously, they required drainage to relieve symptoms or to improve renal function. Surgeons need to be aware of this complication and include its possible occurrence in the informed consent obtained prior to injection.