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.

Open ureteroneocystostomy after failed endoscopic injection with three different bulking agents for the treatment of vesicoureteral reflux

BACKGROUND/PURPOSE

To evaluate the success rate of open ureteroneocystostomy (UNC) after failed endoscopic treatment of vesicoureteral reflux (VUR) in children and to discuss the reasons for failure under the light of histopathological findings.

METHODS

The clinical data of 371 patients who underwent endoscopic injection for VUR at our institution for the treatment of VUR between January 2008 and January 2014 were reviewed. Patients who were submitted to open ureteral reimplantation following failed endoscopic injection were included in the study.

RESULTS

Among 371 patients, 34 (49 ureters) were submitted to open UNC (9.1%). There were 22 female and 12 male patients. Three different injection materials were used; dextranomer/hyaluronic acid in 29, carbon-coated beans in 7 and polyacrylate polyalchohol copolymer in 13. Histological study revealed that the injected material was identified in 34 ureters as malpositioned. Control VCUG 6 months after UNC showed complete resolution in 46 of 47 ureters (97.87%).

CONCLUSIONS

Previous endoscopic injection, although causing difficulty in dissection to some degree, does not alter the success rate of UNC. According to the histopathological findings, the cause of failure of injection seems to be attributable to incorrect plane of injection or leakage of the agent after injection.

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.