Endoscopic treatment of vesicoureteral reflux after kidney transplantation: outcomes and predictive factors of clinical and radiological success

Purpose This study aimed to identify and describe the outcomes of different endoscopic treatments and the predictive factors affecting success in the treatment of symptomatic vesicoureteral reflux (VUR) after kidney transplantation. Methods Patients who had undergone endoscopic injection treatment for symptomatic VUR detected by VCUG with at least 1-year follow-up were included in the study. Patients with dysfunctional and/or obstructive voiding patterns were excluded from the study. We retrospectively evaluated the patient's characteristics, operative information about the type of injection (one, two, or four-point) and the bulking agent (DX-HA, PPC), and perioperative data. Clinical success was defined as no febrile UTI, and radiological success was defined as the absence of VUR in VCUG 3 months after the operation. Clinical success, radiological success, and encountered complications were statistically analyzed. Results A total of 76 patients were included in this study. The one-point, two-point, and four-point injection technique was applied to 32 (42.1%), 13 (17.1%), and 31 (40.7%) of patients, respectively. PPC and DX-HA were used as bulking agents in 54 (71.1%) and 22 (28.9%) patients, respectively. The clinical success rate was 73.7% (n = 56). In logistic regression analysis, a significant efficacy of the four-point technique was observed in the univariate analysis of clinical success (p = 0.042). The radiological success rate was 40.8% (n = 31). In the logistic regression analysis, DX-HA and PPC radiological success was attained in 4 (18.1%) and 27 (50%) patients, respectively (p = 0.01). Ureterovesical junction (UV) stricture developed in 5 (6.5%) patients. There was no difference between injection techniques and bulking agents in terms of the development of UV stricture (p = 0.32; p = 0.08). Conclusion The success of endoscopic treatment in patients with VUR after kidney transplantation can be increased by multiple injections. Furthermore, PPC can be used to obtain a higher radiological success.