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.