Minimally Invasive Treatment of Vesico-ureteral Reflux Using Endoscopic Injection of Polyacrylate-Polyalcohol Copolymer (Vantris) in Patients After Kidney Transplantation.

BACKGROUND: Urinary tract infections (UTIs) are the most common infectious complications among kidney recipients. They occur due to the lack of an effective antireflux mechanism in the majority of techniques used during kidney transplantation. Subureteral injection of tissue bulking substance is a feasible alternative to open ureteral reimplantation. This paper, to the best of the authors' knowledge, is the first to evaluate the application of polyacrylate/polyalcohol copolymer (Vantris) as the agent for minimally invasive VUR treatment. MATERIALS AND METHODS: Between January 2018 and February 2019, 7 patients presenting with recurrent UTIs and the diagnosis of VUR (vesico-ureteric reflux) after kidney transplantation were enrolled in the study. Patients qualified for the study underwent cystoscopy and, if possible, minimally invasive, endoscopic subureteral application of 1 mL of polyacrylate/polyalcohol copolymer according to the subureteral transurethral injection (STING) technique. RESULTS: Endoscopic subureteral injection of tissue bulking substance (polyacrylate/polyalcohol copolymer) was successfully performed in 6 patients. In 1 patient it could not be completed because of an inconvenient location of the neo-orifice. In 4 patients (57%) no reduction of the reflux grade was observed in follow-up imaging. The number of UTIs in the follow-up was significantly reduced in 6 of 7 patients (86%) after polyacrylate/polyalcohol copolymer subureteral injection. CONCLUSIONS: Endoscopic treatment of VUR with polyacrylate/polyalcohol copolymer is an effective and safe method as a first-line treatment for patients with recurrent UTIs after kidney transplantation. To obtain clear conclusions, however, it is necessary to study a larger number of patients with a longer follow-up period after surgery.