Percutaneous endopyelotomy for secondary ureteropelvic junction obstruction: Prognostic factors affecting late recurrence

Objective. To determine prognostic variables which influence late recurrence after initially successful percutaneous endopyelotomy for secondary ureteropelvic junction obstruction (UPJO). Material and methods. Between July 1987 and March 2002, 67 patients with secondary UPJO were treated with percutaneous endopyelotomy at our center. Long-term follow-up data were available for 50 patients with initially successful results ( 42 after a single treatment and eight after repeated endopyelotomy). Follow-up excretory urography and diuretic renal scans were performed for objective evaluation. Late recurrence was diagnosed if obstruction developed after > 1 year of follow-up. Univariate (Kaplan-Meier method) and multivariate ( Cox regression model) analyses of pre-, peri- and postoperative factors were carried out for detection of significant variables affecting the late recurrence rate. Results. The follow-up period ranged from 1.27 to 13.85 years ( mean 6 +/- 4.3 years). Late recurrence of UPJO was observed in seven cases (14%): 4/42 initially successful cases (9.5%) and 3/8 cases of repeated endopyelotomy (37.5%). In univariate analysis, the significant factors were severity of stenosis at the UPJ ( p = 0.04), preoperative serum creatinine ( p = 0.04), repetition of endopyelotomy ( p = 0.03) and development of postoperative complications ( p = 0.02). In multivariate analysis, all of the above factors, with the exception of severity of stenosis at the UPJ, were independent significant factors affecting late recurrence. Conclusions. As late recurrence was observed in 14% of cases after percutaneous endopyelotomy, long-term follow-up is needed, especially in patients with elevated preoperative serum creatinine, those in whom postoperative complications developed and those in whom a first attempt at endopyelotomy failed.