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

Pneumovesicoscopic Transvesical Ureteric Reimplantation for the Correction of Congenital Lower Ureteric Anomalies in Children: A Regional Arabian Gulf Multicenter Retrospective Experience

OBJECTIVE

To report and compare the outcomes of 3 different techniques of pneumovesicoscopic ureteric reimplantation applied in children.

METHODS

The study included 178 renal units in 105 patients who underwent pneumovesicoscopic reimplantation between January 2016 and October 2021. Presentation, indication for surgery, surgical technique, operative time, operative details, days of hospitalization and catheterization, and outcome were retrieved from patients' electronic records.

RESULTS

The collected data was revised, coded, tabulated, and fed into the computer using the Statistical Package for Social Science (SPSS 25). Data were presented, and the appropriate statistical analysis was performed according to the type of data obtained for each parameter.

CONCLUSION

The pneumovesicoscopic approach to ureteric reimplantation is not inferior to the data reported in the literature for open approach in terms of success rate (94%). In addition, pneumovesicoscopy permits the evaluation of the trigonal anatomy in situ, which can have a significant impact on the selection of the most appropriate surgical technique.

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 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.

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.

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.

Endoscopic Correction of Reflux Utilizing Polyacrylate Polyalcohol Bulking Copolymer (Vantris) as a Tissue Augmenting Substance: Lessons Learned Over the 10 Years of Experience

Objectives: To prove the hypothesis that modifying the endoscopic correction of vesicoureteral reflux (VUR) technique (STING procedure) and sharpening its contraindications, lead to increased success rate and decline in the complication rate. Materials and Methods: All patients that underwent endoscopic correction of VUR utilizing Vantris were divided into two groups according to procedure date; before 2015 and 2015-2019. Indication for treatment included persistent high-grade VUR or breakthrough infections. Contraindications included voiding dysfunction, active infection and since 2015 suspicion for obstructive/refluxing ureterovesical junction (UVJ) presented by "beak" sign on voiding cystourethrography (VCUG). Follow-up regiment included ultrasound and VCUG at predetermined intervals. Results: The first group included 215 (158 girls and 57 boys) children with mean age of 4.8 ± 2.8 years who underwent endoscopic correction between 2009 and 2015 and the second group included 42 children (28 girls and 14 boys) with mean age of 3.9 ± 2.1 years who underwent surgery between 2015 and 2019. In the first group, VUR was unilateral in 74 patients and bilateral in 132 comprising 338 renal refluxing units. In the second group, VUR was unilateral in 14 patients and bilateral in 30 comprising 74 RRUs. In the first group reflux was corrected in 317 (94.9%) RRUs after a single injection, after the second in 7 (2.1%) RRUs. In seven (2.1%) RRUs, reflux downgraded to Grade I-II. Three RRUs (0.9%) failed endoscopic correction and required ureteral reimplantation. Nine (2.7%) RRUs developed UVJ obstruction. In the second group reflux was corrected in 61 (82.4%) RRUs after a single injection, after the second in 12 (16.2%) RRUs. In one (1.4%) RRU, endoscopic correction failed and required ureteral reimplantation. None of the patients developed UVJ obstruction. Reflux correction has led to the significant decrease of febrile urinary tract infection (UTI) in both groups. Conclusions: Our data indicate that endoscopic injection utilizing Vantris is safe and long durable procedure. Although utilizing the proper technique and contraindication criteria, the rates of post procedural VUJ obstruction is null.

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.

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.

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.

Idiosyncratic reaction after injection of polyacrylate - polyalcohol copolymer

Context:

Polyacrylate-polyalcohol copolymer is a synthetic product, non-biodegradable, with low rate of therapeutic failure and lower incidence of reactions at the site of injection, when compared to biodegradable agents. We report an unprecedent, exuberant and persistent inflammatory reaction following injection of that substance.

Patient:

a 17 years-old patient with vesico-ureteral reflux and complete pyelocaliceal right duplication was submitted to treatment with polyacrylate-polyalcohol copolymer (STING technique). In the seventh day of post-operatory, she presented intense dysuria and hypogastric pain, without laboratory exams alterations; a symptomatic treatment was started. After two months, the symptoms persisted and an ultrasound detected thickening of bladder wall close to the uretero-vesical junction. After that exam, a cystostopic biopsy showed epithelial hyperplasia with increased edema of lamina propria, suggesting an adverse reaction to the polymer. After four months, there was complete remission, but the reflux persisted with the same grade.

Hypothesis:

This is an unprecedent reaction following injection of this copolymer. The presence of characteristics such as absence of infection, temporal relation between treatment and beginning of symptoms, and detection of epithelial hyperplasia at the local of injection reinforce the hypothesis of association of the substance and adverse reaction. In that patient, important complains motivated early investigation of urinary tract, that confirmed those aspects. Maybe if that reaction had occurred in patients with lower capacity of expression (such as in infants) it would be unnoticed.

Incidence of ureterovesical obstruction and Cohen antireflux surgery after Deflux® treatment for vesicoureteric reflux

AIM

The purpose of this study was to determine the incidence of ureteric obstruction (UB) and requirement for Cohen antireflux surgery (CAS) after Deflux^Ⓡ treatment (DT) for vesicoureteric reflux (VUR).

METHODS

Between 2011 and 2017, 494 ureters (VUR severity ≤ grade III: N=291 or >grade IV: N=203) were treated by DT at a mean age of 4.5 (range: 0.2-24) years. Epidural Catheter Assistance (ECA) was used to exclude UB by injecting diluted indigo carmine solution (1-3mL) into an epidural catheter inserted into a ureter after DT and confirming dye flow within 15min. ECA+: N=181 ureters; ECA-: N=313 ureters.

RESULTS

In ECA+, UB was detected in 5/181 (2.7%) ureters (grade II: N=1, III: N=3, and IV: N=1) treated by leaving the ECA catheter in situ overnight (N=4) or double J stent (DJS) insertion for 1month (N=2). After mean follow-up of 1.9years, one grade III DJS case has residual grade II VUR. In ECA-, 3/313 (0.9%) cases developed UB. One resolved, and one required DJS. CAS was required for 17/494 (3.4%) ureters and hindered by DT in 5/17 (29.4%) ureters. All are sequelae-free after mean follow-up of 1.8years.

CONCLUSIONS

UB may be more frequent than reported (3.3% versus 0.6%-1.8%). ECA identifies potential UB.

TYPE OF STUDY

Treatment study.

LEVEL OF EVIDENCE

Level III.

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.

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.

Subureteral Injection with Small-Size Dextranomer/Hyaluronic Acid Copolymer: Is It Really Efficient?

The aim of this study was to evaluate the clinical results of patients with vesicoureteral reflux, which were treated with subureteral injection of small-size (80–120 μm) dextranomer/hyaluronic acid copolymer (Dx/HA). Data of 75 children (105 renal units) who underwent STING procedure with small-size Dx/HA for the treatment of vesicoureteral reflux (VUR) in our clinic between 2008 and 2012 were retrospectively analyzed. Preoperative reflux grade and side, injection indication, postoperative urinary infections and urinary symptoms, voiding cystourethrogram, and renal scintigraphy results were evaluated. The success rate of the procedure was 100% in patients with grades 1 and 2 reflux, 91% in patients with grade 3 reflux, and 82.6% in patients with grade 4. Overall success rate of the treated patients was 97%. Endoscopic subureteric injection with Dx/HA procedure has become a reasonable minimally invasive alternative technique to open surgery, long-term antibiotic prophylaxis, and surveillance modalities in treatment of VUR in terms of easy application, low costs and complication rates, and high success rates. Injection material composed of small-size dextranomer microspheres seems superior to normal size Dx/HA, together with offering similar success with low cost.

Endoscopic treatment of grades IV and V vesicoureteral reflux with two bulking substances: Dextranomer hyaluronic acid copolymer versus polyacrylate polyalcohol copolymer in children

PURPOSE

We aimed at evaluating the efficacy and complications of two bulking substances: dextranomer/hyaluronic acid copolymer(Dx/Ha;Dexell®) versus polyacrylate polyalcohol copolymer(PPC;Vantris®) in subureteric injection treatment of children with high grades (grades IV-V) vesicoureteral reflux(VUR).

METHODS

Data of patients undergoing endoscopic treatment of high grade VUR (January 2009-August 2015) were retrospectively investigated. Patients with high grade VUR caused by posterior urethral valve, duplex system, paraureteral diverticula and neurogenic bladder were excluded. Classical subureteric injection method (STING) was used. Seventy-three children (45 girls and 28 boys) who had 88 refluxing renal units (RRUs) with grades IV-V VUR (n=64/n=24) underwent endoscopic treatment using Dx/Ha (n=63 RRUs) and PPC (n=25 RRUs).

RESULTS

Mean age of patients in Dx/Ha and PPC groups were 6 (3) and 6 (3.75) year (p=0.81), and volumes of these substances given were 1.3 (1) and 1 (0.5) mL (p=0.003), respectively. Overall, for the first endoscopic injection, success rate of grades IV-V VUR per RRU was 53.9% with Dx/Ha, compared to 80% in PPC-injected group, (p=0.024). Late ureterovesical junction obstruction developed only in one patient in PPC-injected group. No ureteral obstruction was observed in Dx/Ha-injected group.

CONCLUSIONS

Endoscopic injection of PPC resulted in significantly higher success rate, compared to Dx/Ha in subureteric injection treatment of children with high grade VUR. However, the development of late ureterovesical junction obstruction should also be taken into account in PPC injection.

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.

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.

Efficacy of dextranomer hyaluronic acid and polyacrylamide hydrogel in endoscopic treatment of vesicoureteral reflux: A comparative study

INTRODUCTION

Various bulking agents are available for vesicoureteral reflux (VUR) endoscopic treatment, but their inconsistent success rates and costs are concerns for urologists. Recently, polyacrylamide hydrogel (PAHG) has been shown to have a good overall success rate, which seems comparable to dextranomer hyaluronic acid (Dx/HA), currently the most popular bulking agent. Our objective was to compare the short-term success rate of PAHG and Dx/HA for VUR endoscopic treatment in children.

METHODS

We performed a prospective non-randomized study using PAHG and Dx/HA to treat VUR grades I to IV in pediatric patients. All patients underwent endoscopic sub-ureteric injection of PAHG or Dx/HA, using the double-HIT technique, followed by a 3-month postoperative renal ultrasound and voiding cystourethrogram. Treatment success was defined as the absence of de novo or worsening hydronephrosis and absence of VUR.

RESULTS

A total of 90 pediatric patients underwent an endoscopic injection: 45 patients (78 ureters) with PAHG and 45 patients (71 ureters) with Dx/HA. The mean injected volume of PAHG and Dx/HA was 1.1 mL and 1.0 mL, respectively. The overall success rate 3 months after a single treatment was 73.1% for PAHG and 77.5% for Dx/HA. Postoperatively, 1 patient in each group presented with acute pyelonephritis and 2 patients in the Dx/HA group developed symptomatic ureteral obstruction.

CONCLUSION

Success rates of PAGH and Dx/HA in endoscopic injections for VUR treatment were comparable. The rate of resolution obtained with Dx/HA was equivalent to those previously published. The lower cost of PAHG makes it an interesting option.

Postoperative ureteral obstruction after endoscopic treatment for vesicoureteral reflux

Purpose

We undertook this study to evaluate the incidence, risk factors, management, and outcome of postoperative ureteral obstruction after endoscopic treatment for vesicoureteral reflux (VUR).

Materials and Methods

Ninety patients undergoing endoscopic treatment for VUR were retrospectively reviewed and classified into two groups according to ureteral obstruction: the nonobstruction group (83 cases, 122 ureters; mean age, 7.0±2.8 years) and the obstruction group (7 cases, 10 ureters; mean age, 6.2±8.1 years). We analyzed the following factors: age, sex, injection material, laterality, voiding dysfunction, constipation, renal scarring, preoperative and postoperative ultrasound findings, endoscopic findings, injection number, and injection volume. Additionally, we reviewed the clinical manifestations, natural course, management, and outcome of ureteral obstruction after endoscopic treatment.

Results

The incidence of ureteral obstruction after endoscopic treatment was 7.6% (10/132 ureters). The type of bulking agent used and injection volume tended to be associated with ureteral obstruction. However, no significant risk factors for obstruction were identified between the two groups. Three patients showed no symptoms or signs after the onset of ureteral obstruction. Most of the patients with ureteral obstruction experienced spontaneous resolution within 1 month with conservative therapy. Two patients required temporary ureteral stents to release the ureteral obstruction.

Conclusions

In our experience, the incidence of ureteral obstruction was slightly higher than in previous reports. Our study identified no predictive risk factors for developing ureteral obstruction after endoscopic treatment. Although most of the ureteral obstructions resolved spontaneously within 1 month, some cases required drainage to relieve symptoms or to prevent renal function deterioration.

Late ureteral obstruction after endoscopic treatment of vesicoureteral reflux with polyacrylate polyalcohol copolymer

OBJECTIVE

To investigate the incidence and presentation of ureteral obstruction after endoscopic injection of polyacrylate polyalcohol copolymer (PPC) for the treatment of vesicoureteral reflux, and to analyze its possible causes, together with histopathologic assessment.

PATIENTS AND METHODS

The data of 189 patients who underwent endoscopic injection of PPC between May 2011 and December 2013 were retrospectively reviewed. After the injection, patients were followed up by urinalysis and ultrasonography monthly for 3 months. Control voiding cystouretrography was performed in the third postoperative month. Patients were then followed up by ultrasound every 3 months. If a new-onset hydroureteronephrosis (HUN) was observed, control ultrasound was performed monthly to follow the change in the degree of HUN. If a moderate or severe HUN was observed, technetium-99m mercaptoacetyltriglycine or dimercaptosuccinic acid scintigraphy was performed. For patients who needed open surgery, Cohen ureteroneocystostomy was performed. The distal 1 cm of the ureters was resected and examined histopathologically.

RESULTS

One hundred eighty-nine patients with 268 refluxing ureters underwent endoscopic injection of PPC. Ureteral obstruction was observed in 3 ureters (1.1%), in 3 female patients of whom the degrees of reflux were grade 4, 5, and 5, respectively. Obstruction showed late onset in all 3 patients. Manifestations of obstruction included pain in 2 patients and recurrent febrile urinary tract infection with loss of function in scintigraphy in 1. All 3 patients underwent open ureteroneocystostomy.

CONCLUSION

PPC may cause ureteral obstruction several months or even years after injection. Patients who undergo endoscopic treatment of PPC need long-term follow-up, despite reflux showing complete resolution.

Endoscopic correction of vesicoureteral reflux in children with a solitary kidney: the risk of obstruction

PURPOSE

We aimed to review patients with a solitary kidney and ipsilateral vesicoureteral reflux (VUR) who underwent endoscopic correction of VUR (ECVUR) and to evaluate the prevalence of obstruction in this group of patients.

MATERIALS AND METHODS

We retrospectively reviewed the files of all patients who underwent ECVUR at our center between January 2000 and June 2011. Only patients with a solitary kidney and ipsilateral VUR were included.

RESULTS

Thirteen patients met our criteria. Two patients (15.38%) developed obstruction post-ECVUR. Both patients developed anuria in the first 24 h after surgery and required intervention. Two patients (15.38%) had increasing hydroureteronephrosis that was discovered on follow-up ultrasound, with no symptoms or signs of obstruction. Both were managed conservatively.

CONCLUSION

Our results showed a higher percentage of obstruction post-ECVUR in patients with a solitary kidney (15.38%), who required immediate intervention. Thus, we recommend giving clear instructions to parents of patients with VUR and a solitary kidney post-ECVUR before discharge from the hospital regarding decreased urine output and loin pain. We recommend a follow-up ultrasound to rule out obstruction and detect new-onset hydronephrosis.

Postoperative ureteral obstruction after endoscopic treatment of vesicoureteral reflux with polyacrylate polyalcohol copolymer (Vantris®)

PURPOSE

To investigate the incidence and presentations of ureteral obstruction following periureteral injection of polyacrylate polyalcohol copolymer (PPC) for the treatment of vesicoureteral reflux (VUR).

MATERIALS AND METHODS

From Jan 2010 to Dec 2012, 88 patients (28 male, 60 female) with 128 renal refluxing units (RRU), 131 ureters and a mean age of 6.7 ± 5.9 years (range: 4 months to 32 years) underwent endoscopic correction of their VUR, using PPC. Exclusion criteria were dysmorphic appearing distal ureter, extravesical position of the ureteral orifice, persistent urethral obstruction (e.g. after previous valve ablation) and severe bladder trabeculation, making ureteral orifice unidentifiable. Patients were followed up by ultrasound one month after the injection and then every three months. Cystography was performed 3 months post-operation. Mean follow-up time was 13.1 ± 6.8 months (range: 3-27 months).

RESULTS

Two patterns of obstruction were observed: early, during the first 3-4 days post-operation, in four patients (4 ureters; 3%) which was associated with transient hydroureteronephrosis (HUN) in 2 patients (2 ureters; 1.5%); and late-onset obstruction in 3 patients (4 ureters; 3%) which appeared 3 months to 1 year after surgery. It manifested itself by urinary tract infection and uremia in one patient with bilateral obstruction but was asymptomatic in the other two. Early obstruction was managed expectantly and resolved in 3-12 months; however, late-onset obstruction needed catheter placement or open ureteroneocystostomy.

CONCLUSIONS

Patients who undergo endoscopic treatment for their VUR using PPC need long-term follow up until the safety of this substance is confirmed.

Acute and delayed vesicoureteral obstruction after endoscopic treatment of primary vesicoureteral reflux with dextranomer/hyaluronic acid copolymer: why and how to manage

OBJECTIVE

To present our cases of ureteral obstruction after endoscopic treatment of vesicoureteral reflux (VUR) with dextranomer/hyaluronic acid (Dx/HA).

PATIENTS AND METHODS

We collected data from patients who had suffered ureteral obstruction after endoscopic treatment of VUR with Dx/HA in our institution.

RESULTS

From April 2002 to April 2011 we treated endoscopically 475 ureters with VUR, and detected 5 ureteral obstructions. Median age at reflux treatment was 39 months. Reflux grade before treatment was III in one patient and IV in four. Three ureterovesical junctions (UVJ) were blocked after a second endoscopic treatment. The median of Dx/HA injected was 1 ml (0.6-1.1). In two patients ureteral obstruction presented acutely and was treated with a ureteral stent. In the other three, the ureteral obstruction appeared gradually and was detected by ultrasound scans and MAG3 diuretic renogram; one underwent nephrectomy because of poor renal function, and the other two were treated with endoscopic dilatation of the UVJ. In all these patients both reflux and obstructions have resolved.

CONCLUSIONS

On preoperative cystography, three of the patients had a narrowed distal ureter, and probably had a refluxing and obstructive megaureter. Other causes are not clear, except for those patients with acute presentation in whom edema of the UVJ was found. Ureteral obstruction after endoscopic treatment of VUR is rare. Endoscopic intervention such as ureteral stent placement or high-pressure balloon dilatation of the UVJ has good results as a treatment of acute and delayed obstruction.

Results of Treatment of Grades IV and V Vesicoureteral Reflux with Endoscopic Injection of Polyacrylate Polyalcohol Copolymer

PURPOSE

Here we report the results of a review of a prospectively maintained database of the use polyacrylate polyalcohol copolymer (PPC) injection to correct grades IV and V VUR.

MATERIALS AND METHODS

All children with grades IV and V primary VUR that presented with febrile urinary tract infection while on prophylaxis, in a 3-year period, were treated with a sub-ureteral injection of PPC. Institutional ethical approval was obtained. Exclusion criteria were incomplete bladder emptying documented on videourodynamic study, ureteral duplication, paraureteral diverticula, and poor ureteral emptying observed during fluoroscopy and previous open surgical or endoscopic treatment. Pre- and post-operative evaluation included urinalysis, renal and bladder ultrasonography, DMSA scan, and videourodynamic studies.

RESULTS

Thirty-three children [36 renal units (RU)] were included with a median age of 57 months (range 7-108). There were 18 boys and 15 girls. Thirty RU had grade IV and 6 grade V VUR. Median follow-up time was 32 months (range 7-58). Reflux was cured in 32/36 RU with the first injection, but another two patients were reimplanted because of dilatation. Complications included early urinary tract infection in seven children, transient lower urinary tract symptoms in five children. Progressive ureteral dilatation was noted in four children and was treated with insertion of a double J stent. Two of these children eventually required an ureteroneocystostomy.

CONCLUSION

The use of PPC to treat grades IV and V vesicoureteral reflux in young children has an overall success rate of 83.3%. Persistent ureteral dilatation was present in 11% associated with high injection volume. Future studies will attempt to maintain a high success rate reducing the volume of injection and the incidence of dilatation.

Symptomatic bilateral delayed partial ureteral obstruction after bilateral endoscopic correction of vesicoureteral reflux with dextranomer/hyaluronic acid polymer

Endoscopic correction of vesicoureteral reflux using dextranomer/hyaluronic acid copolymer (Deflux) is a widely used technique. Complications are uncommon, and ureteral obstruction occurs particularly infrequently. We present a case of delayed symptomatic partial bilateral ureteral obstruction after bilateral high-volume (>1.0 mL) Deflux injections that required surgical repair 16 months after injection (Clavien classification IIIb.) Bilateral delayed obstruction after endoscopic correction of vesicoureteral reflux has not been previously reported. Previous reports of immediate and delayed ureteral obstruction after Deflux injection are reviewed.