A comparison of the double hydrodistention implantation technique (HIT) and the HIT with a polyacrylate/polyalcohol copolymer (PPC) for the endoscopic treatment of primary vesicoureteral reflux

Interventions for primary vesicoureteric reflux

BACKGROUND

Vesicoureteric reflux (VUR) results in urine passing retrograde up the ureter. Urinary tract infections (UTI) associated with VUR have been considered a cause of permanent renal parenchymal damage in children with VUR. Management has been directed at preventing UTI by antibiotic prophylaxis and/or surgical correction of VUR. This is an update of a review first published in 2004 and updated in 2007 and 2011.

OBJECTIVES

The aim of this review was to evaluate the available evidence for both benefits and harms of the currently available treatment options for primary VUR: operative, non-operative or no intervention.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 3 May 2018 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings, and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

RCTs in any language comparing any treatment of VUR and any combination of therapies.

DATA COLLECTION AND ANALYSIS

Two authors independently determined study eligibility, assessed quality and extracted data. Dichotomous outcomes were expressed as risk ratios (RR) with 95% confidence intervals (CI) and continuous data as mean differences (MD) with 95% CI. Data were pooled using the random effects model.

MAIN RESULTS

Thirty four studies involving 4001 children were included. Interventions included; long-term low-dose antibiotics, surgical reimplantation of ureters, endoscopic injection treatment, probiotics, cranberry products, circumcision, and oxybutynin. Interventions were used alone and in combinations. The quality of conduct and reporting of these studies was variable, with many studies omitting crucial methodological information used to assess the risk of bias. Only four of the 34 studies were considered at low risk of bias across all fields of study quality. The majority of studies had many areas of uncertainty in the risk of bias fields, reflecting missing detail rather than stated poor design.Low-dose antibiotic prophylaxis compared to no treatment/placebo may make little or no difference to the risk of repeat symptomatic UTI (9 studies, 1667 children: RR 0.77, 95% CI 0.54 to 1.09; low certainty evidence) and febrile UTI (RR 0.83, 95% CI 0.56 to 1.21; low certainty evidence) at one to two years. At one to three years, antibiotic prophylaxis made little or no difference to the risk of new or progressive renal damage on DMSA scan (8 studies, 1503 children: RR 0.73, 95% CI 0.33 to 1.61; low certainty evidence). Adverse events were reported in four studies with little or no difference between treatment groups (1056 children: RR 0.94, 95% CI 0.81 to 1.08; ), but antibiotics increased the likelihood of bacterial drug resistance threefold (187 UTIs: RR 2.97, 95% CI 1.54 to 5.74; moderate certainty evidence).Seven studies compared long-term antibiotic prophylaxis alone with surgical reimplantation of ureters plus antibiotics, but only two reported the outcome febrile UTI (429 children). Surgery plus antibiotic treatment may reduce the risk of repeat febrile UTI by 57% (RR 0.43, 95% CI 0.27 to 0.70; moderate certainty evidence). There was little or no difference in the risk of new kidney defects detected using intravenous pyelogram at 4 to 5 years (4 studies, 572 children, RR 1.09, 95% CI 0.79 to 1.49; moderate certainty evidence)Four studies compared endoscopic injection with antibiotics alone and three reported the outcome febrile UTI. This analysis showed little or no difference in the risk of febrile UTI with endoscopic injection compared to antibiotics (RR 0.74, 95% CI 0.31 to 1.78; low certainty evidence). Four studies involving 425 children compared two different materials for endoscopic injection under the ureters (polydimethylsiloxane (Macroplastique) versus dextranomer/hyaluronic acid polymer (Deflux), glutaraldehyde cross-linked (GAX) collagen (GAX) 35 versus GAX 65 and Deflux versus polyacrylate polyalcohol copolymer (VANTRIS)) but only one study (255 children, low certainty evidence) had the outcome of febrile UTI and it reported no difference between the materials. All four studies reported rates of resolution of VUR, and the two studies comparing Macroplastique with Deflux showed that Macroplastique was probably superior to dextranomer/hyaluronic acid polymer (3 months: RR 0.50, 95% CI 0.33 to 0.78; 12 months: RR 0.54 95% CI 0.35 to 0.83; low certainty evidence)Two studies compared probiotic treatment with antibiotics and showed little or no difference in risk of repeat symptomatic UTI (RR 0.82 95% CI 0.56 to 1.21; low certainty evidence)Single studies compared circumcision with antibiotics, cranberry products with no treatment, oxybutynin with placebo, two different surgical techniques and endoscopic injection with no treatment.

AUTHORS' CONCLUSIONS

Compared with no treatment, the use of long-term, low-dose antibiotics may make little or no difference to the number of repeat symptomatic and febrile UTIs in children with VUR (low certainty evidence). Considerable variation in the study designs and subsequent findings prevented drawing firm conclusions on efficacy of antibiotic treatment.The added benefit of surgical or endoscopic correction of VUR over antibiotic treatment alone remains unclear since few studies comparing the same treatment and with relevant clinical outcomes were available for analysis.

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.

Comparison of results of endoscopic correction of vesicoureteral reflux in children using two bulking substances: Dextranomer/hyaluronic acid copolymer (Deflux) versus polyacrylate-polyalcohol copolymer (Vantris)

BACKGROUND

Endoscopic correction of vesicoureteral reflux (VUR) in children offers minimally invasive management and is widely used as a first-line procedure for all grades of reflux. However, there is debate about which tissue-augmenting substance is the best to use. The aim of this study was to evaluate the efficacy of two bulking substances, Deflux (Dx/HA) and Vantris (PPC), for endoscopic treatment of VUR in children.

METHODS

From 2009 to 2012, 65 children (50 girls and 15 boys) aged 1.45-9.9 years (mean 4.85 ± 2.52) underwent endoscopic correction of VUR using Deflux. VUR was unilateral in 31 patients and bilateral in 34 patients, comprising 108 renal refluxing units (RRUs) grades: II in 52, III in 47, IV in 7, and V in 2. From 2012, 68 children (43 girls and 25 boys) aged 0.6-17.9 years (mean 4.89 ± 3.46) were treated with Vantris. VUR was unilateral in 33 and bilateral in 35 patients, comprising 109 RRUs grades: II in 48, III in 29, IV in 13, and V in 19. Voiding cystourethrogram was done 3 months after procedure.

RESULTS

All patients completed follow-up (summary Table). With Deflux, reflux resolved in almost 93% of RRUs after two procedures (in 63% after first injection), with Vantris, VUR was corrected in the same percentage after one procedure.

DISCUSSION

The success rate with Deflux ranges between 68% and 92% (only 50-70% after single injection). The reported possibility of reflux recurrence after successful Deflux treatment, and the need for repeated injection led to introduction of the new substance Vantris. The results of a multi-centre survey published in 2014 showed that reflux is corrected in more than 90% of cases after single PPC injection. Our results with PPC confirm a high level of reflux resolution.

CONCLUSIONS

Our data show that Vantris injection is a safe and effective procedure for treating all grades of VUR with good clinical outcome, and provides a higher and almost complete level of reflux resolution after first injection compared with Deflux.