For the treatment of vesicoureteral reflux (VUR), endoscopic injection of bulking agents has emerged as a viable option to antibacterial prophylaxis and ureteral reimplantation. Despite its reputation as a safe and effective technique, multiple studies revealed incidences of ureteral obstruction (UO) following endoscopic VUR repair. For a review, researchers assessed the current VUR literature in order to quantify the risk of UO following endoscopic injection of various chemicals, as well as the influence of injection method and implant amount. Twenty-five publications were found that included detailed information on 64 females and 32 males (ages 7 months to 48 years) who developed UO following endoscopic treatment of VUR with dextranomer/hyaluronic acid (Dx/HA), polyacrylate polyalcohol (PP), polydimethylsiloxane (PDMS), calcium hydroxyapatite (CaHA), polytetrafluoroethylene (PTFE), or collagen. The observed incidence of UO varied across various materials: Dx/HA (0.5–6.1%), PP (1.1–1.6%), PDMS (2.5–10.0%), CaHA (1.0%), and PTFE (0.3% ). Following subureteric transurethral injection (STING), intraurethral hydrodistention implantation method (HIT), combination HIT/STING, and double HIT, postoperative UO was documented. The amount injected varied greatly, depending on the bulking agent used: Dx/HA (0.3–3.0 mL), PP (0.3–1.2 mL), PDMS (1.0–2.2 mL), CaHA (0.4–0.6 mL), and PTFE (1.5–2.0 mL). UO occurred just after the operation or up to 63 months afterward. On follow-up imaging, more than half of the patients had asymptomatic hydroureteronephrosis, whereas the others had symptoms of acute UO or fever.
UO is an uncommon consequence after endoscopic VUR correction, occurring in less than 1% of treated patients and appearing to be unrelated to the injected material, volume, or method. Long-term monitoring is necessary, as asymptomatic or delayed UO can develop, resulting in renal function impairment.
Reference:link.springer.com/article/10.1007/s11934-019-0913-5
