Risk Factors For Failure Of Endoscopic Balloon Dilatation Of Primary Obstructive Megaureter. Single Centre 12-Year Experience With 123 Cases.

To review our experience with >100 patients with primary obstructive megaureter (POM) undergoing Endoscopic Balloon Dilatation (EBD) and a follow-up of up to 12 years, and determine potential risk factors for failure. Our hypotheses were that EBD allows for long-term treatment in >80% of patients, and its effectiveness decreases in more severe cases. Retrospective study of 123 consecutive patients (131 ureters) undergoing EBD from 2009 to 2021. Indications for EBD included symptoms, worsening dilatation, and/or renal function impairment. Clinical characteristics, complications, and outcomes, including those in the patients with >5-year follow-up, were described. Preoperative and intraoperative markers of severity chosen a priori were tested as risk factors for failure. Failure was defined as the need for ureteral reimplantation after EBD. EBD was feasible in 121/123 (98%) patients, regardless of age. After a median follow-up of 38 (9-143) months, EBD was successful in 84.5% of cases. Failures generally occurred in the first year after EBD and were seldom associated with permanent loss of renal function. Of the 66 patients with follow-up >5-year, EBD was successful in 56. No preoperative characteristic proved to be a risk factor for failure. The intraoperative absence of a ring was the only significant risk factor for failure, OR 117.86 (95CI 6.27-2215.84) Conclusions: EBD was feasible and definitive treatment in 85% of our cases, regardless of age. Since this study did not identify preoperative factors to help the clinicians in patient selection, we consider EBD a viable initial procedure in all patients with POM who require surgical intervention, especially in infants.