Endoscopic Injection of Dextranomer/Hyaluronic Acid as First Line Treatment in 851 Consecutive Children with High Grade Vesicoureteral Reflux: Efficacy and Long-Term Results

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.

A novel endoscopic approach for management of hutch diverticulum concomitant vesicoureteral reflux with dextranomer/hyaluronic acid copolymer injection

INTRODUCTION

There are various treatment options for symptomatic bladder diverticulum, including robotic-assisted laparoscopic bladder diverticulectomy, open and endoscopic techniques. But, to date, the optimal surgical technique remains unclear.

OBJECTIVE

To present the preliminary long-term follow-up results of a novel technique of dextranomer/hyaluronic acid copolymer (Deflux) plus autologous blood injection for correction of hutch diverticulum in patients with concomitant vesicoureteral reflux (VUR).

PATIENT AND METHOD

We retrospectively reviewed four patients who had hutch diverticulum with concomitant VUR and had undergone submucosal Deflux following autologous blood injection. Patients with neurogenic bladder, posterior urethral valve, or voiding dysfunction were excluded from the study. Success was defined as the resolution of the diverticulum, hydronephrosis, and hydroureter on ultrasonography at a 3-month follow-up and long-term symptom-free period.

RESULTS

Four patients with hutch diverticula were included. The median age at the time of surgery was 6.1 (range 3-8) years. Three of them had unilateral VUR, and one had bilateral VUR. During the procedure, a mean of 0.625 ml Deflux plus a mean of 1.25 ml autologous blood were injected submucosally for correction of VUR. Additionally, a mean of 1.62 ml Deflux plus a mean of 1.75 ml autologous blood were injected submucosally to occlude the diverticulum. The median follow-up was 4.6 (range 4-8) years. This method had excellent success in all patients in the current study with no postoperative complications such as febrile urinary tract infection, or diverticulum, hydroureter, or hydronephrosis in follow-up ultrasounds.

CONCLUSIONS

Submucosal injection of Deflux plus autologous blood injection can be a successful endoscopic intervention for treatments of hutch diverticulum in patients with concomitant VUR. Deflux injection can be a simple and cost-effective technique.

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.

Comparison of polyacrylate polyalcohol copolymer (PPC) and dextranomer/hyaluronic acid (Dx/HA) for treatment of vesicoureteral reflux. A systematic review and meta-analysis

PURPOSE

Our study aimed to compare the efficacy of polyacrylate polyalcohol copolymer and Dextranomer-Hyaluronic Acid for endoscopic treatment of vesicoureteral reflux.

MATERIAL AND METHODS

MEDLINE, EMBASE, Scopus, Web of science, Ovid, Cochrane databases, Google scholar have been searched for studies published until January 2022 in any language. Studies that compared the success rate for endoscopic treatment of vesicoureteral reflux in children with two bulking agents, namely, "polyacrylate polyalcohol copolymer." and "Dextranomer-Hyaluronic Acid" were included for this analysis.

RESULTS

Nine studies were included in data synthesis for this meta-analysis. Pooled data with a total of 763 ureters in PPC group and 718 ureters in Dx/HA group indicated that ureters in PPC group were more likely to undergo complete reflux resolution than Dx/HA (OR 3.80, 95% CI: 2.71; 5.31). Among subgroup of patients with high grade reflux, PPC injection had more resolution rate compared to Dx/HA patients (OR: 2.92, 95% CI: 1.19-7.16). In total, 95.81% of the PPC group and 86.52% of the Dx/HA group experienced success after the third injection. However a concerning complication of endoscopic treatment which is ureterovesical junction obstruction (UVJO) was more prevalent in PPC group. So the possible benefits arising from endoscopic treatment with PPC could be offset by the costs of re-implantation surgery or stenting in the case of UVJO.

CONCLUSION

These data indicate that PPC injection for vesicoureteral reflux treatment was associated with a higher success rate, but concerningly, UVJO incidence was higher in the PPC group which might negate the possible benefits of PPC injection However, due to the lack of studies with long-term follow-up, we couldn't reach a definitive conclusion about the superiority of one of the bulking agents over the other.

Vesicoscopic Cross-Trigonal Ureteral Reimplantation for Vesicoureteral Reflux: Intermediate Results

For the treatment of vesicoureteral reflux, the introduction of vesicoscopic procedures offers new perspectives for improving patient comfort and quality. Our aim was to examine whether minimally invasive vesicoscopic cross-trigonal ureteral reimplantation (VCUR) would meet expectations. Between 2012 and 2021, 99 girls and 35 boys with high-grade vesicoureteral reflux (VUR) underwent VCUR. For two boys, we failed to establish the pneumovesicum, leading to conversion to open surgery. The mean age was 4.5 years, ranging from 10 months to 18 years. VCUR was successfully performed in 132 patients, including 75 patients with bilateral VUR and 12 children with double ureters with unilateral or bilateral VUR, corresponding to a total of 229 operated ureters. The mean time of operation was 151 min for all patients. There were no perioperative complications, with the exception of three cases of pneumoperitoneum without consequences. Postoperatively, we recognized three cases of acute hydronephrosis, two of them required transient drainage. Three patients developed extravasation of urine after the postoperative removal of the transurethral catheter, rapidly resolved by new drainage. In two patients, we combined VCUR with laparoscopic heminephrectomy and opposite laparoscopic nephrectomy, respectively. Overall, mean postoperative hospital stay was 4.2 days. We observed recurrent VUR in seven ureters, resulting in a success rate for VCUR of 96.9%. These results demonstrate the feasibility of VCUR and its potential to displace open surgery with high safety and wide applicability.

Non-Animal Stabilized Hyaluronic Acid/Dextranomer Gel (NASHA/Dx, Deflux) for Endoscopic Treatment of Vesicoureteral Reflux: What Have We Learned Over the Last 20 Years?

Non-animal stabilized hyaluronic acid/dextranomer gel (Deflux; NASHA/Dx) was developed as a treatment for vesicoureteral reflux (VUR) in the 1990s. To mark 20 years since the US approval of this agent, we reviewed its properties, best practice for application, and the available clinical safety and efficacy data. Long-term or randomized, controlled studies of treatment with NASHA/Dx have reported VUR resolution rates of 59%-100% with low rates of febrile urinary tract infection post-treatment (4%-25%), indicating long-term protection of the kidneys. An individualized approach VUR management is advocated, and NASHA/Dx is a viable option for many patients requiring intervention.

Armamentarium to treat primary vesicoureteral reflux in children

Primary vesicoureteral reflux often spontaneously resolves in children. However, in select patients, untreated reflux can contribute to recurrent pyelonephritis leading to irreversible renal damage. Management is therefore based on a given child's likelihood of recurrent urinary tract infections and risk of subsequent renal parenchymal injury. Therapeutic options for urinary reflux are diverse, ranging from observation with or without continuous low-dose antibiotic prophylaxis to a variety of operative interventions.

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.

Mid-Term Safety and Efficacy of the Modified Double Hydrodistention Implantation Technique (HIT), Termed Systematic Multi-Site HIT (SMHIT), for Patients with Primary Vesicoureteral Reflux

Purpose

To evaluate the treatment outcomes and postoperative complications associated with the systematic multi-site hydrodistention implantation technique (SMHIT) for primary vesicoureteral reflux (VUR) and to determine its mid-term efficacy and safety.

Patients and Methods

We retrospectively reviewed the data for 17 ureters from 12 consecutive children, aged ≥1 year, with grade II-IV reflux and a history of febrile urinary tract infections (FUTI), who underwent a single-session of SMHIT. The primary outcome was the absence of postoperative FUTI (clinical success). The secondary outcome was improvement in reflux to grade 0-I on postoperative voiding cystourethrography (radiographic success).

Results

Five and 7 children had bilateral and unilateral reflux, respectively. Reflux was categorized as grade II, III, and IV reflux in 2, 12, and 3 ureters, respectively. Seven of 10 (70%) toilet-trained children had bladder-bowel dysfunction (BBD) preoperatively. The SMHIT was performed for all patients, after which BBD improved. The mean postoperative follow-up period was 6 years and 9 months. The clinical success rate was 100%. Radiographic success was achieved in 16/17 ureters (94%) at 3-4 months, 17/17 (100%) ureters at 1 year, and 17/17 (100%) ureters at 3 years postoperatively. Major complications did not develop postoperatively.

Conclusion

When prioritizing treatment of concomitant BBD in children with primary VUR and avoiding dextranomer/hyaluronic acid injection therapy in contraindicated children according to the Food and Drug Administration recommendations, a single-session of SMHIT may be as effective and safe in the mid-term as performing open anti-reflux surgery.

High-grade vesicoureteral reflux in infants: Our experience with endoscopic subureteric injections

BACKGROUND

Vesicoureteral reflux (VUR) is the most common urological anomaly in pediatric patients. Management options for VUR vary from continuous antibiotic prophylaxis (CAP) to surgery via either endoscopic subureteric injection of a bulking agent or open anti-reflux surgery. In this study, we assess the efficacy of subureteric injections of Dextranomer/Hyaluronic acid Copolymer (Deflux) in managing primary VUR in infant patients with high-grade VUR.

METHODS

From 2010 to 2015, children less than 1-year-old with primary high-grade VUR were observed prospectively following the administration of endoscopic subureteric injections of Dextranomer/Hyaluronic Acid Copolymer (Deflux). The diagnosis of VUR was based on MCUG, and all patients underwent a holistic clinical, laboratory, and radiological assessment before and after the intervention. Complete success was defined as the resolution of VUR on follow up 1 year post-operatively.

RESULTS

A total of 30 infants (50 renal units) with high-grade VUR (grades IV and V) were included in the study. The mean age at surgery was 6.3 ± 2.5 months. Most of the patients presented with a urinary tract infection (90%). Complete symptomatic relief was achieved in 27 patients (90%) at the first post-operative follow-up. Forty-four renal units received one injection, while six required a second injection as they did not meet our treatment success criteria. No patients required a third injection or referral for open surgery.

CONCLUSION

Endoscopic injection of Dextranomer/Hyaluronic acid Copolymer (Deflux) at the vesicoureteral junction is an effective minimally invasive intervention to treat high grades VUR (IV-V) infants.

Evolving surgical management of pediatric vesicoureteral reflux: is open ureteral reimplantation still the 'Gold Standard'?

Vesicoureteral reflux, the retrograde flow of urine from the bladder into the upper urinary tract, is one of the most common urologic diagnoses in the pediatric population. Once detected, therapeutic options for urinary reflux are diverse, ranging from observation with or without continuous low-dose prophylactic antibiotics to a variety of operative interventions. While a standardized algorithm is lacking, it is generally accepted that management be tailored to individual patients based on various factors including age, likelihood of spontaneous resolution, risk of subsequent urinary tract infections with renal parenchymal injury, and parental preference. Anti-reflux surgery may be necessary in children with persistent reflux, renal scarring or recurrent pyelonephritis after optimization of bladder and bowel habits. Open, laparoscopic/robot-assisted and endoscopic approaches are all successful in correcting reflux and have been shown to reduce the incidence of febrile urinary tract infections.

Proprietary non-animal stabilized hyaluronic acid/dextranomer gel (NASHA/Dx) for endoscopic treatment of grade IV vesicoureteral reflux: Long-term observational study

BACKGROUND

Since 1993, children aged >1 year with persistent grade III-V vesicoureteral reflux (VUR) and febrile urinary tract infections (UTIs) attending Uppsala University Hospital have undergone endoscopic injection with proprietary non-animal stabilized hyaluronic acid/dextranomer gel (NASHA/Dx; Deflux®).

OBJECTIVE

Investigate long-term incidence of UTI, bladder dysfunction, ureteral reimplantation and overall clinical findings following endoscopic injection of NASHA/Dx.

STUDY DESIGN

Children with grade IV VUR diagnosed by voiding cystourethrogram (VCUG) and dilating VUR persisting for >1 year were included in this study. 15-25 years after endoscopic treatment, patients' hospital charts were studied. Information on bladder function and UTIs was obtained via questionnaire, 8-18 years after endoscopic treatment.

RESULTS

185 patients (69 boys, 116 girls) were included in the study; 237 grade IV VUR ureters were treated. All study patients were diagnosed with VUR after a febrile UTI (i.e. pyelonephritis). According to the last voiding cystourethrogram, 69% of ureters showed a positive response (VUR grade 0-I), 7% had VUR grade II and 23% had VUR grade ≥ III. 46 patients (25%) required ureteral reimplantation during follow-up. Among patients treated during the second 5-year period compared with the first (1998-2003 versus 1993-1998), there was a significant decrease in the rate of ureteral reimplantation (31% vs 16%; p = 0.0365). This difference may be attributable to developments over time in the injection technique. UTIs occurred in 30 patients (21% of the evaluable population): 28 females and 2 males. Febrile UTIs were reported in 14 patients (10%), all females. Forty-nine patients (34%) had bladder problems (e.g. underactivity, overactivity, incontinence). Five patients underwent ureteral reimplantation 'late', 6-10 years after the last endoscopic injection. In one male patient, calcification around the NASHA/Dx implantation site was observed during routine examination 2 years after endoscopic treatment; no intervention was required. No safety issues were observed in the remaining 97% of the study population.

CONCLUSIONS

This study represents the longest published follow-up of Grade IV VUR patients undergoing endoscopic treatment. Three-quarters of patients did not need ureteral reimplantation. Optimal injection technique and higher injection volume were associated with a reduced ureteral reimplantation rate. Treatment with NASHA/Dx was durable and well tolerated: long-term risks of UTI, bladder dysfunction and recurrent VUR were low.

Long-Term Clinical Outcomes and Parental Satisfaction After Dextranomer/Hyaluronic Acid (Dx/HA) Injection for Primary Vesicoureteral Reflux

Purpose: Endoscopic dextranomer/hyaluronic acid (Dx/HA) injection is a common treatment for vesicoureteral reflux (VUR) with excellent reported short-term clinical success rates. Long-term outcomes are less well-defined. We assessed long-term outcomes and parental satisfaction after Dx/HA injection for primary VUR with >5-year follow-up. Materials and Methods: Families of all patients who underwent Dx/HA injection for primary VUR at our institution between 2008 and 2012 were contacted for telephone interview. Data collected by phone included parental satisfaction and presence and severity of UTIs pre-operatively and post-operatively. Patient demographics, radiographic VUR data, need for secondary surgery, and surgical indications were obtained through chart review. Results: Five hundred and seventy-five patients underwent Dx/HA injection for primary VUR between 2008 and 2012. Ninety-nine (17.2%) of these patients' parents were successfully contacted and interviewed. Median follow-up time from surgery to survey was 8.4 (IQR 6.8-9.6) years. Secondary surgery was performed in 13/99 (13.1%), most commonly repeat Dx/HA injection. Seven patients (7.1%) underwent secondary Dx/HA injection for persistent VUR without UTIs at a median of 0.35 (IQR 0.33-0.77) years post-operatively. Five patients (5.1%) underwent Dx/HA injection (n = 3) or ureteral reimplantation (n = 2) for VUR with febrile UTIs (fUTIs) at a median of 2.2 (IQR 1.3-5.1) years. One patient had ureteral reimplantation for symptomatic obstruction 2.8 years after initial surgery. Only 3/99 (3.0%) required open or laparoscopic surgery after Dx/HA injection. Eighty-three families (84.7%) reported ≥1 fUTIs pre-operatively. Of these, only 9/83 (10.8%) reported fUTIs post-operatively, for an overall clinical success rate of 89.2%. Clinical success was 93.1% in patients whose pre-operative fUTIs were treated outpatient and 80.0% in those hospitalized at least once for fUTI treatment pre-operatively. Ninety-four percent of parents were highly satisfied, 2.4% partially satisfied, and 3.5% dissatisfied. Conclusions: Endoscopic injection with Dx/HA for primary VUR appears to have good long-term clinical success rates and high parental satisfaction, mirroring our previously reported short-term results. Post-operative ureteral obstruction is rare but may occur years post-operatively, justifying initial sonographic surveillance, and repeat imaging in symptomatic patients.

Robotic Ureteral Reconstruction in the Pediatric Population

Robot-assisted laparoscopic (RAL) surgery is a safe, minimally invasive technique that has become more widely used in pediatric urology over recent decades. With several advantages over standard laparoscopy, robotic surgery is particularly well-suited to reconstructive surgery involving delicate structures like the ureter. A robotic approach provides excellent access to and visualization of the ureter at all levels. Common applications include upper ureteral reconstruction (e.g., pyeloplasty, ureteropelvic junction polypectomy, ureterocalicostomy, and high uretero-ureterostomy in duplex systems), mid-ureteral reconstruction (e.g., mid uretero-ureterostomy for stricture or polyp), and lower ureteral reconstruction (e.g., ureteral reimplantation and lower ureter-ureterostomy in duplex systems). Herein, we describe each of these robotic procedures in detail.

Pediatric voiding cystourethrography: An essential examination for urologists but a terrible experience for children

Voiding cystourethrography is the most important fluoroscopic examination in pediatric urology for the investigation of lower urogenital tract diseases, such as vesicoureteral reflux or urethral stricture. However, this invasive procedure imposes a significant burden on children and their parents, and recently there has been a paradigm shift in the diagnosis and treatment of vesicoureteral reflux. In the 2011 revision, the American Academy of Pediatrics guidelines on urinary tract infection recommended abandoning routine voiding cystourethrography after the first febrile urinary tract infection. In 2014, the randomized intervention for children with vesicoureteral reflux study recommended discontinuation of routine continuous antibiotic prophylaxis for vesicoureteral reflux. The time is now ripe to radically reconsider indications for voiding cystourethrography and the procedure itself.