Delayed-onset ureteral obstruction after endoscopic dextranomer/hyaluronic acid copolymer (Deflux) injection for treatment of vesicoureteral reflux in children: a case series

Successful rescue pneumovesicoscopic surgery for post-Deflux® vesicoureteral junction obstruction

BACKGROUND

Vesicoureteral junction (VUJ) obstruction after Deflux® subureteral injection for vesicoureteral reflux (VUR) is rare and minimally invasive management has not been reported. This work investigated the patients who underwent Deflux® injection for VUR and identified those with subsequent VUJ obstruction.

METHODS

Medical records of matched patients from October 2003 to March 2022 were reviewed, and parameters were retrospectively studied. All patients underwent Deflux® injection. The injection was performed under general anesthesia using the same manner. For patients complicated with VUJ obstruction, the symptoms, signs, management, images, renal ultrasounds, Tc-99m dimercaptosuccinic acid renal scintigraphy, histology of VUJ region, and outcomes were documented and reported. VUJ stenosis was diagnosed by performing renal ultrasound and magnetic resonance imaging.

RESULTS

Totally 407 patients (554 ureterorenal units) received Dx/HA injections for VUR. VUJ obstruction was found in three patients (four ureterorenal units). Originally, three were grade V VUR, and one was grade IV. The repeated injection was not a risk factor for VUJ obstruction. The overall incidence of VUJ obstruction post-Dx/HA injection was 0.7% by ureter. The incidences were 0%, 0.75%, and 2.25% for grade I-III, IV, and V VUR, respectively. After the initial conversion case of pneumovesicoscopic ureteral reimplantation, the procedure was performed smoothly and successfully in the two following cases.

CONCLUSIONS

Pneumovesicoscopic ureteral reimplantation offers an alternative for VUJ obstruction following Dx/HA injection for VUR. Fibrosis and foreign-body reaction may influence the feasibility. High-grade VUR and young age of injection were related to VUJ obstruction.

Endoscopic injection of bulking agents in pediatric vesicoureteral reflux: a narrative review of the literature

In the last 20 years, endoscopic injection (EI) has affirmed as a valid alternative to open surgery for management of pediatric vesicoureteral reflux (VUR). This study aimed to investigate and discuss some debated aspects such as indications, bulking agents and comparison, techniques of injection and comparison, predictive factors of success, use in specific situations. EI is minimally invasive, well accepted by patients and families, with short learning curve and low-morbidity profile. It provides reflux resolution rates approaching those of open reimplantation, ranging from 69 to 100%. Obviously, the success rate may be influenced by several factors. Recently, it is adopted as first-line therapy also in high grade reflux or complex anatomy such as duplex, bladder diverticula, ectopic ureters. The two most used materials for injection are Deflux and Vantris. The first is absorbable, easier to inject, has lower risk of obstruction, but can lose efficacy over time. The second is non-absorbable, more difficult to inject, has higher risk of obstruction, but it is potentially more durable. The two main techniques are STING and HIT. To date, the ideal material and technique of injection has not yet clearly established, but the choice remains dependent on surgeon's preference and experience.

A systematic review & meta-analysis comparing outcomes of endoscopic treatment of primary vesico ureteric reflux in children with polyacrylate poly alcohol copolymer versus dextranomer hyaluranic acid

BACKGROUND & AIMS

There are conflicting reports on the efficacy of bulking agents for vesico ureteric reflux (VUR). In this meta-analysis we have compared the outcomes of endoscopic treatment with polyacrylate polyalcohol copolymer (PPC) and dextranomer hyaluronic acid (DxHA).

METHODS

A systematic review of publications between 2010 and 2020 was conducted covering databases like PUBMED, MEDLINE etc. for (endoscopic treatment) AND (VUR) AND (PPC OR DxHA) AND (recurrence OR complications). PRISMA guidelines were followed and only comparative studies were included. Outcomes were early success defined as absence of VUR in voiding cystourethrogram at 3-months followup, urinary tract infections (UTI) and occurrence of vesico-ureteric-junction obstruction (VUJO). Risk of bias was analysed with Robvis tool and odds-ratios were compared with Revman-3.0.

RESULTS

Among nine studies (heterogeneity; I 2 69-79%) all cleared the risk of bias assessment. There was no significant difference in high grade VUR (p = 0.94) between PPC (40%) and DxHA (43%). Success rate after single injection was significantly higher (p = 0.0001) at 86% (477/555) for PPC vs 69% (474/685) for DxHA. UTI rate between PPC (12%) and DxHA (14.6%) was not statistically significant (p = 0.54). VUJO rate between PPC (3.9%) and DxHA (0.8%) was also not significantly different (p = 0.47). Significantly lesser volume (p = 0.02) was used for PPC (0.7 ml) compared to DxHA (0.9 ml).

CONCLUSION

Reflux resolution was significantly higher with PPC than DxHA. Postinjection UTI/VUJO incidence was not significantly different between them. Limitation of this meta-analysis was heterogeneity & small number of articles. Further studies should focus on long-term outcomes and cost-effectiveness.

Endoscopic treatment of primary vesicoureteral reflux in children with two different bulking agents, high success and low complication rates: Comparison of Dexell and Vantris

INTRODUCTION AND OBJECTIVES

To compare the results in terms of efficacy and safety of the endoscopic management for vesicoureteral reflux (VUR) in two different standardized primary VUR cohorts treated with Dexell and Vantris.

PATIENTS

128 refluxing renal units (RRU) in 87 patients with primary VUR (64 females, 23 males). Patients with secondary VUR and severe bladder and bowel dysfunction were excluded. A total of 22 continent children with mild bladder-bowel dysfunction underwent bladder-bowel training before the implantation. All procedures were performed in the presence of sterile urine using a conventional subureteral transurethral injection technique.

RESULTS

There were no statistically significant differences between groups in terms of mean age, sex, RRU side, ^99mTc-DMSA uptake, and reflux grade. The overall resolution rates based on the number of RRUs for up to three endoscopic treatments were 80% (56/70) in Dexell group and 94.8% (55/58) in Vantris group (P = .012). No postoperative recurrences or vesicoureteral junction obstructions were seen in any group.

CONCLUSIONS

Dexell and Vantris provided an effective and safe endoscopic VUR treatment in the early and mid-term follow up of children with primary VUR. The effectiveness of these substances, which can produce different mass effects with different particle sizes, in safe VUR resolution, needs further investigations.

Endoscopic treatment of primary vesicoureteral reflux in children with two different bulking agents, high success and low complication rates: comparison of Dexell and Vantris

INTRODUCTION AND OBJECTIVES

To compare the results in terms of efficacy and safety of the endoscopic management for vesicoureteral reflux (VUR) in two different standardized primary VUR cohorts treated with Dexell and Vantris.

PATIENTS

128 refluxing renal units (RRU) in 87 patients with primary VUR (64 females, 23 males). Patients with secondary VUR and severe bladder and bowel dysfunction were excluded. A total of 22 continent children with mild bladder-bowel dysfunction underwent bladder-bowel training before the implantation. All procedures were performed in the presence of sterile urine using a conventional subureteral transurethral injection technique.

RESULTS

There were no statistically significant differences between groups in terms of mean age, sex, RRU side, 99mTc-DMSA uptake, and reflux grade. The overall resolution rates based on the number of RRUs for up to three endoscopic treatments were 80% (56/70) in Dexell group and 94.8% (55/58) in Vantris group (p = 0.012). No postoperative recurrences or vesicoureteral junction obstructions were seen in any group.

CONCLUSIONS

Dexell and Vantris provided an effective and safe endoscopic VUR treatment in the early and mid-term follow up of children with primary VUR. The effectiveness of these substances, which can produce different mass effects with different particle sizes, in safe VUR resolution, needs further investigations.

Incidence and risk factors for calcification after dextranomer/hyaluronic acid (Dx/HA) copolymer injection for vesicoureteral reflux

INTRODUCTION

Since the first case of dextranomer/hyaluronic acid (Dx/HA) implant calcification in 2008, concern about the long-term sequelae of Dx/HA injection has been growing. According to previous reports, the incidence of Dx/HA calcification 4 years after injection would be around 2%.

AIM

The primary aim was to estimate the incidence of Dx/HA implant calcification after endoscopic treatment of vesicoureteral reflux in pediatric patients. Secondary objectives were to establish risk factors and to perform a survival analysis after Dx/HA injection.

STUDY DESIGN

Patients undergoing Dx/HA endoscopic injection from 2007 to 2014 were prospectively registered. The database included clinical, surgical and radiological outcomes. Patients that showed Dx/HA implant calcification during follow-up were compared to those who did not. Univariable and survival statistical analyses were performed.

RESULTS

30 implants calcified over 355 ureters endoscopically treated. Age at first treatment was lower in patients with implant calcification (2.4 ± 1.3 years vs 3.6 ± 2.5 years; p < 0.005). The risk of implant calcification was 8.45% (95% CI: 5.96-11.85%). Median follow-up was 7.6 years (IQR: 5.2-9.5). The incidence rate was 12.06 cases per 1000 ureters-year. The period of highest hazard of implant calcification was between 3 and 5 years after injection. The only risk factor related to implant calcification was the age at first injection: relative risk of implant calcification was 4.4 (95% CI: 1.6 to 12.4; p = 0.002) for patients first treated before the age of 3.5 years.

DISCUSSION

The risk and the incidence rate of Dx/HA implant calcification were higher than previous data. The period of highest hazard and detection of implant calcification were consistent with previous reports. Patients first treated before the age of 3.5 had shorter survival time without implant calcification. These are the first data about risk factors and survival function of Dx/HA implant calcification. However, our conclusions about the clinical significance of Dx/HA implant calcification were limited because the patients with implant calcification were asymptomatic. Further studies with larger sample and longer follow-up should confirm the clinical significance and life-long tendency of Dx/HA implant calcification.

CONCLUSIONS

The risk and the incidence rate of Dx/HA implant calcification were higher than expected. The hazard of calcification was higher between 3 and 5 years after injection. The risk was especially higher in patients treated before the age of 3.5. Caution should be taken not to confuse implant calcifications with ureteric stones. A 5-year follow-up would set a better understanding of the actual incidence and clinical significance of implant calcification.

Asymptomatic bilateral delayed ureteral obstruction following dextranomer/hyaluronic acid copolymer (Deflux) injection for vesicoureteral reflux.: A case report

We here present a case of a 4-year-old girl who exhibited an asymptomatic bilateral de novo hydroureteronephrosis seven months after undergoing endoscopic treatment for bilateral vesicoureteral reflux. The child underwent an open bilateral reimplantation. Intraoperatively, a 14 mm nodule on the right and a 16 mm on the left located periureteral orifice were observed. When a small incision was made on nodules, a yellowish-white mucinous fluid flowed out.

Brazilian consensus on vesicoureteral reflux-recommendations for clinical practice

Introduction

Vesicoureteral Reflux (VUR) is characterized by a retrograde flow of urine from the bladder into the ureters and kidneys. It is one of the most common urinary tract anomalies and the major cause of urinary tract infection (UTI) in the first years of life. If not properly diagnosed and treated can lead to recurrent UTI, renal scar and, in severe cases, to end stage renal disease. Despite recent advances in scientific and technological knowledge, evaluation and treatment of VUR is still controversial and there is still considerable heterogeneity in evaluation methods and therapeutic approaches. The aim of the present consensus is to give a practical orientation on how to evaluate and treat VUR.

Methods

The board of Pediatric Urology of the Brazilian Society of Urology joined a group of experts and reviewed all important issues on Vesicoureteral Reflux evaluation and treatment and elaborated a draft of the document. On November 2017 the panel met to review, discuss and write a consensus document.

Results and Discussion

Vesicoureteral Reflux is a common and challenging problem in children. Children presenting with Vesicoureteral Reflux require careful evaluation and treatment to avoid future urinary tract infections and kidney scars. The panel addressed recommendations on up to date choice of diagnosis evaluation and therapies.

Distal Ureteral Calculus or Deflux Calcification?

Background: There have been >50,000 dextranomer-hyaluronic acid implants performed since 2001, and each has the potential to calcify. Although they are most often asymptomatic, these calcifications may mimic large distal ureteral calculi and are often misidentified on CT performed for suspected urolithiasis or other complaints. Case Presentation: We report the case of a 21-year-old woman who presented with symptoms consistent with obstructive uropathy who was reported to have bilateral ureteral-vesicular junction calculi on abdominal CT evaluation. On further questioning she relayed the history of a vague urologic procedure as a child but was unable to characterize it further. On the basis of her relatively mild symptoms, urinalysis and renal ultrasonography were obtained demonstrating bilateral ureteral jets and she was diagnosed with nonobstructing bilateral dextranomer-hyaluronic acid calcifications and a presumed urinary tract infection that resolved with empiric antibiotic therapy. Conclusion: Accurate diagnosis of implant calcification is critical to effective therapy and avoiding unnecessary radiation or anesthesia. This diagnosis should be suspected with radiologically demonstrated large ureteral calculi but relatively mild presenting symptoms. As dextranomer-hyaluronic acid implantation is routinely performed in young patients it is also possible that this relevant history will not be reported.

When does vesicoureteral reflux in pediatric kidney transplant patients need treatment?

PURPOSE

The treatment of VUR in children with UTI has changed significantly, due to studies showing that antibiotic prophylaxis does not decrease renal scarring. As children with kidney transplants are at higher risk for UTI, we investigated if select patients with renal transplant VUR could be managed without surgery.

MATERIALS AND METHODS

A total of 18 patients with VUR into their renal grafts were identified, and 319 patients underwent transplantation from 2006 to 2016. The cause for the detection of the VUR, treatment, and graft function was reviewed.

RESULTS

Six boys and 12 girls were identified, 13 of whom had grade 3 or 4 VUR into the renal graft. Nine patients presented with hydronephrosis or abnormal renal biopsy: eight were successfully managed with antibiotic prophylaxis and bladder training, one developed UTI and underwent Dx/HA subureteric injection. Nine patients presented with recurrent febrile UTI, only one was successfully managed without surgery. Only 2 of 9 (22%) patients who underwent Dx/HA injection had resolution of their reflux. Of the remaining seven, five required open ureteral reimplantation (two for obstruction), one lost the graft due to rejection, and one had significant hydronephrosis. eGFR was similar between the hydronephrosis, UTI, and abnormal renal biopsy groups at all times.

CONCLUSION

Patients with transplant VUR and recurrent febrile UTI are more likely to require surgical therapy, but the complication and failure rate for Dx/HA injection is significant. Patients with transplant VUR without febrile UTI can be successfully managed with bladder training and temporary antibiotic prophylaxis.

What are the predictive factors leading to ureteral obstruction following endoscopic correction of VUR in the pediatric population?

BACKGROUND

It is extremely important to not only address the short-term success following endoscopic correction of vesicoureteral reflux (VUR) but also the long-term efficacy and safety of the tissue augmenting substance utilized for endoscopic correction.

OBJECTIVE

This study retrospectively evaluated all cases of ureterovesical junction (UVJ) obstruction following endoscopic treatment of VUR over the last 5 years utilizing two tissue augmenting substances, with special emphasis on the safety of Vantris^®, and performed clinical and histological review of these patients.

METHODS

The study population comprised 2495 patients who underwent endoscopic correction of VUR utilizing Deflux^® (1790) and Vantris^® (705). Tissue sections were stained with hematoxylin & eosin and trichrome, and examined under a light microscope. Nine primary obstructive megaureters after ureteral re-implantation served as controls.

RESULTS

Nine (0.5%) children (three female and six male) in the Deflux group and nine (1.3%) (five females and four males) in the Vantris group developed UVJ obstruction and required ureteral re-implantation. Obstruction developed during the period ranging 2-49 months (average 16 months) following endoscopic correction. The primary reflux grade was III in seven, IV in six, and V in six children. The mean volume of the injected material in all obstructed patients was 1.2 ± 0.6 cc (mean ± SD). Histopathological analysis revealed a pseudocapsule composed of fibrous tissue and foreign-body giant cells surrounding the Vantris implant in all patients. The distal part of the ureters demonstrated significant ureteral dilatation without ureteral fibrosis. In all patients, additional biopsies from the muscularis propria adjacent to the injection site were examined and showed no significant abnormalities. There was an increased collagen deposition in the juxtavesical segment of the obstructive ureters following Deflux and Vantris injections, and of primary obstructive megaureter. No significant difference was found in the tissue response between Deflux and Vantris patients and controls. Statistical analysis of the nonhomogeneous population demonstrated higher obstruction rates in patients from the Vantris group. However, no statistical difference was demonstrated regarding the obstruction rate in the homogenous group with relation to gender, age and reflux grade group of patients. Moreover, univariate analysis revealed that Grade V reflux, the presence of beak sign on the reviewed pretreatment, and inflamed bladder mucosa upon injection were significant independent risk factors leading to obstruction.

DISCUSSION

This study suggested that the underlining ureteral pathology lead to UVJ obstruction following Vantris injection. There was increased collagen deposition in the juxtavesical segment of the obstructive ureters following Vantris injection. Furthermore, these findings were similar to those discovered in patients who underwent endoscopic correction with Deflux, and in patients who required ureteral reimplantation due to primary obstructive megaureter. Additional biopsies from the muscularis propria adjacent to the injection site showed no significant abnormalities, ironing out the fact that Vantris did not led to adverse tissue reaction following injection. Univariate analysis further ironed out the hypothesis that underlying ureteral pathology was responsible for the increased incidence of UVJ obstruction and demonstrated that Grade V reflux, the presence of beak sign on the reviewed pretreatment VCUG, and inflamed bladder mucosa upon injection were significant independent risk factors leading to obstruction.

CONCLUSION

Data showed that Vantris injection did not lead to any different ureteral fibrosis or inflammatory changes to the tissue augmenting substances utilized in past and present clinical practice, and therefore did not seem to increase the incidence of UVJ obstruction. High reflux grade, presence of obstructive/refluxing megaureter and inflamed bladder mucosa were the only statistically significant and independent predictive factors for UVJ obstruction following endoscopic correction of VUR.

Changing bulking agent may require change in injection volume for endoscopic treatment of vesicoureteral reflux

Introduction:

Various bulking agents were utilized for endoscopic correction of VUR. A study reviewing multi-institutional data showed that the amount of injection material has increased over time with the purpose of improving success rates, which also resulted in costs. We noticed an opposite trend in our center since we started using a new bulking agent. The aim of this study was to evaluate evolution of our practice with different bulking agents.

Patients and Methods:

Records of VUR patients who underwent subureteric injection with polyacrylate polyalcohol copolymer (PPC) and dextronomere hyaluronic acide (DxHA) between 2005 and 2014 were reviewed. Variation of different parameters throughout the study period was evaluated along with the success rate. Success was defined as complete resolution of reflux.

Results:

A total of 260 patients with 384 refluxing units were included. The success rate was higher in PPC group compared to DxHA group. There was no statistically significant difference between years regarding distribution of VUR grade, body weight, patient height, and age in PPC group. Despite significant reduction in injection volume, success rate did not decrease through the years with PPC.

Conclusion:

Different bulking agents may require different injection volumes to achieve the same success rate in endoscopic treatment of vesicoureteral reflux. Habits gained with previous experience using other materials should be revised while using a new agent.

The effect of prior endoscopic correction of vesicoureteral reflux on open ureteral reimplantation: Surgical outcomes and costs

INTRODUCTION

Endoscopic injection of a bulking agent is a common first-line approach to the treatment of vesicoureteral reflux (VUR). While early outcomes are comparable to open ureteroneocystotomy, 5-25% of children will eventually develop recurrent reflux necessitating repeat injections or open ureteral reimplantation.

OBJECTIVE

To determine whether prior endoscopic injection of a bulking agent impacts outcomes of subsequent open ureteral reimplantation.

STUDY DESIGN

Using a retrospective cohort design, radiographic and clinical outcomes of open ureteral reimplantation were compared between patients with and without prior endoscopic correction of reflux. Surgical and hospitalization data were also compared between groups and a cost comparison was performed to assess differences in healthcare costs between the two cohorts. Units of analysis included total ureters or total patients. For certain variables, subanalysis of unilateral versus bilateral reimplantation was included.

RESULTS

A total of 258 patients underwent open reimplantation for VUR between 2007 and 2016 by five pediatric urologists. Final analysis (see Summary Table) included 192 patients with pre-operative and postoperative voiding cystourethrogram (VCUG) and follow-up data at a median 4.95 months. Among 317 reimplanted refluxing ureters, radiographic resolution was reached in 26/27 (96.3%) patients with and 279/290 (96.2%) without prior endoscopic treatment (P = 0.981). Clinical success was achieved in 17/17 (100%) patients with and 174/175 (99.4%) without prior endoscopic treatment (P = 0.755). There were no statistically significant differences between duration of surgery or length of hospital stay. There were no statistically significant differences between total charges, total costs, and operating room (OR) costs between groups.

DISCUSSION

This study indicated that prior endoscopic injection of a bulking agent did not impact the outcomes or costs of subsequent open ureteroneocystotomy. While prior studies have demonstrated tissue changes associated with injection of a bulking agent, these did not seem to significantly impact the difficulty of later open surgery or the success rates compared to patients who proceeded directly to open correction of reflux.

CONCLUSION

Open ureteral reimplantation for recurrent VUR after failed endoscopic injection of a bulking agent was safe and effective, with comparable outcomes and costs to open surgery in patients without prior endoscopic correction.

New bulking agent for the treatment of vesicoureteral reflux: Polymethylmethacrylate/dextranomer

Purpose

The aim of this study was to report preliminary results of endoscopic treatment of vesicoureteral reflux in children with a single injection of a new bulking agent, cross-linked dextran and polymethylmethacrylate mixture.

Materials and Methods

We performed a single-center, single surgeon, prospective, off-label study using polymethylmethacrylate/dextranomer to treat vesicoureteral reflux. All patients underwent endoscopic injection, followed by renal ultrasound and voiding cystourethrogram at 3 months postoperatively to identify de novo or worsening hydronephrosis and vesicoureteral reflux correction (to Grade 0 or I).

Results

Eighteen patients underwent injection of polymethylmethacrylate/dextranomer at our institution between April 2013 and December 2013. Ten were males and eight were females, with a median age of 58 months (range, 6 months to 5 years). Vesicoureteral reflux was unilateral in three patients and bilateral in 15, for a total of 33 renal refluxing units. Vesicoureteral reflux was Grade I in one renal refluxing unit, Grade II in 12, Grade III in 16, and Grade IV in four. Mean injected volume was 0.86 mL. Reflux was corrected in 23 renal refluxing units (69.7%) according to the 3-month voiding cystourethrogram. Complications included urinary retention in one patient. Mild pyelectasis was noted in one patient at 3 months, which spontaneously resolved 3 months later.

Conclusions

Our short-term data show that polymethylmethacrylate/dextranomer injection can be used to treat vesicoureteral reflux with comparable efficacy to other substances currently used and a low rate of complications. Long-term follow-up is required to confirm the usefulness of this material in treating vesicoureteral reflux.

Endoscopic correction of vesicoureteral reflux in children using polyacrylate-polyalcohol copolymer (Vantris): 5-years of prospective follow-up

Introduction

The endoscopic correction of vesicoureteral reflux (VUR) in children is a currently well accepted therapy in many pediatric urology centers. Polyacrylate-polyalcohol copolymer (PPC), namely Vantris^®, is one of the tissue-augmenting substances used for endoscopic reflux therapy. The aim of this study was to evaluate the results with PPC in children.

Material and methods

From 2012 to 2016, 125 children (73 girls and 52 boys) aged 0.6–17.9 years (mean 4.9 ±3.58) were treated with PPC. VUR was unilateral in 64 and bilateral in 61 patients, comprising 197 renal refluxing units (RRUs) grades: II in 72, III in 50, IV in 33 and V in 42. Of these primary reflux was present in 132 RRUs and 65 were complex cases. Voiding cystourethrogram (VCUG) was done 3 months after procedure.

Results

Follow-up was completed in 89.6% of patients (112 children), and 89.8% of RRUs (177 out of 197). Reflux resolved in 86.4% of RRUs after single injection, in 99.4% after second and in 100% after the third. The only significant, but serious complication observed was late ureteral obstruction after PPC injection correcting high grade reflux, which required ureteral re-implantation. This complication was found in 9 out of 112 children (8%), and in 11 out of 177 RRUs (6.2%), 1.1 -2.9 years (mean 2 ±0.7) after the PPC injection. The longest follow-up reaches 4.5 years.

Conclusions

Our data show that the PPC injection is an effective procedure for treating all grades of VUR with high success rate. However, because of the possibility of late ureteral obstruction, which requires ureteroneocystostomy, long-term follow-up is mandatory.

[Vesicoureteral reflux : Watchful waiting, surgery or antibiotic prophylaxis?]

Primary vesicoureteral reflux (VUR) is a dynamic disease with several factors influencing its course. Therapeutic options range from watchful waiting to open surgery. Multiple risk factors for the development of pyelonephritis are identified, which then determine the decision for the appropriate treatment option. They include age, gender, history of pyelonephritis and renal scarring, bladder and bowel dysfunction (BBD), circumcision status and parental preference. The use of continuous antibiotic prophylaxis (CAP) is becoming increasingly controversial with antibiotic resistance being a major concern. Aggressive treatment of BBD and infant circumcision can greatly reduce the risk for pyelonephritis and should always be considered and discussed. This article is soley concerned with primary VUR.

Endoscopic injection therapy

Since the U.S. Food and Drug Administration approved dextranomer/hyaluronic acid copolymer (Deflux) for the treatment of vesicoureteral reflux, endoscopic injection therapy using Deflux has become a popular alternative to open surgery and continuous antibiotic prophylaxis. Endoscopic correction with Deflux is minimally invasive, well tolerated, and provides cure rates approaching those of open surgery (i.e., approximately 80% in several studies). However, in recent years a less stringent approach to evaluating urinary tract infections (UTIs) and concerns about long-term efficacy and complications associated with endoscopic injection have limited the use of this therapy. In addition, there is little evidence supporting the efficacy of endoscopic injection therapy in preventing UTIs and vesicoureteral reflux-related renal scarring. In this report, we reviewed the current literature regarding endoscopic injection therapy and provided an updated overview of this topic.

The comparison of dextranomer/hyaluronic acid and polyacrylate-polyalcohol copolymers in endoscopic treatment of vesicoureteral reflux

BACKGROUND

Dextranomer/hyaluronic acid (Dx/Ha;Dexell®) and polyacrylate-polyalcohol copolymer (PPC;Vantris®) are the popular tissue-augmenting substances using for the endoscopic injections of vesicoureteral reflux (VUR). The aim of the study is to evaluate and compare Dx/Ha and PPC in terms of effectiveness, injection techniques and complications with special emphasis on vesicoureteral junction obstruction (VUJO).

METHODS

A total of 95 patients who underwent endoscopic VUR treatment between 2009 and 2015 were retrospectively reviewed. The patients were divided into two groups: group 1: Patients underwent endoscopic treatment with PPC (n=50 patients, 70 renal refluxing units) group 2: Patients underwent endoscopic treatment with Dx/Ha (n=45 patients, 74 renal refluxing units).

RESULTS

The overall resolution rates based on the number of renal refluxing units studied was 88.6% and 70.3% in group 1 and group 2, respectively. Resolution rates were significantly better in group 1 compared to group 2. VUJO requiring ureteral reimplantation or stent insertion developed in 7 patients in group 1. No VUJO was observed in group 2. VUJO in group 1 was markedly higher than that in group 2.

CONCLUSIONS

Endoscopic treatment of VUR with PPC promises better resolution rates but higher VUJO rates compared to Dx/Ha.

Prevesical Calcification and Hydronephrosis in a Girl Treated for Vesicoureteral Reflux

The endoscopic STING procedure using Deflux is a common and minimal invasive treatment for vesicoureteral reflux. Herein we present the case of an 11-year-old girl with loin pain and de novo hydronephrosis and megaureter on the left. Ultrasound and plain abdominal X-ray demonstrated a calcification at the ureterovesical junction. She had been treated with Deflux injections 5 years before. The clinical quiz addresses the differential diagnosis, workup, and pathogenesis of calcifications at the ureterovesical junction following endoscopic reflux therapy.

Late ureteral obstruction in an adult who had STING/Teflon in childhood: Should we expect an epidemic?

We present a case of left renal colic in a 25-year-old female patient. She had subureteral injection of Teflon (STING) at the age of 10 due to vesico-ureteral reflux (VUR) disease and recurrent urinary tract infections. Renal colic was the result of late ureteral obstruction due to Teflon-induced periureteral foreign body reaction. To our knowledge, this is the longest interval between STING and ureteral obstruction reported and the first case of delayed ureteral obstruction caused by Teflon. Monitoring the upper tracts of patients after STING should go beyond childhood.

Ureteric patency after Deflux® injection for the treatment of vesicoureteric reflux in children confirmed by a novel epidural catheter-assisted endoscopic technique

PURPOSE

We present EDCAT (epidural catheter-assisted Deflux(®) treatment) for treating vesicoureteral reflux (VUR) and confirming ureteric patency after Deflux(®) treatment.

METHODS

We treated 147 ureters in 101 children (M:F 62:39; VUR ≤ grade III: n = 72; VUR ≥ grade IV: n = 75) using EDCAT between 2011 and 2014. EDCAT involves injecting 1-3 mL of diluted indigo carmine solution through an epidural anesthesia catheter inserted into the Deflux(®)-treated ureter and observing for up to 15 min to confirm patency.

RESULTS

For EDCAT, mean age was 4.9 years and mean operative time was 30.1 ± 12.1 min; overall cure of VUR after initial treatment was 87.7 % for VUR grades I-V, 88.9 % for VUR ≤ grade III, and 86.6 % for VUR ≥ grade IV; VUR was cured in 129/147 after 1 treatment, 7/18 after 2 treatments, 7/11 after 3 treatments, and persistent in 4/4. We experienced 1 case of obstruction after an EDCAT catheter was removed before confirming patency. EDCAT catheters were left overnight in 2 ureters in 2 cases when patency could not be confirmed after 15 min to prevent obstruction. Both did not develop obstruction. Four ureters with recurrence of VUR (all grade ≤ II) are being observed.

CONCLUSION

EDCAT allows ureteric patency to be confirmed immediately and prevents obstruction.

A comparison of calcium hydroxyapatite and dextranomer/hyaluronic Acid for the endoscopic treatment of vesicoureteral reflux

Purpose. Minimal data exists comparing dextranomer/hyaluronic acid (Dx/HA) and calcium hydroxyapatite (CaHA) for the endoscopic treatment of VUR in the hands of a single user. Materials and Methods. We reviewed our consecutive single-user case series of 27 children (42 ureters) receiving endoscopic treatment with CaHA and 21 children (33 ureters) who received Dx/HA injection. Children receiving CaHA injections were divided into two groups of 13 and 14 patients (Coaptite I and II) to assess the learning curve effects. Postoperatively, RBUS and VCUG were performed. Multiple regression analysis was performed to assess statistical significance of success rates. Results. The total CaHA group had a per-ureter success rate (Grade 0) of 52% after one injection. When separated into two cohorts, the single injection per-ureter success rates were 43% for Coaptite I and 62% for Coaptite II. In contrast, the Dx/HA series had a single injection per-ureter success rate (Grade 0) of 78%. Conclusions. Our consecutive case experience shows improved results for Dx/HA compared to CaHA, though the learning curve effects and evolution of injection technique likely played a role in the improved outcomes in the Dx/HA cohort. A randomized controlled multicenter trial would provide the most accurate data comparing these two agents.