Failed Pyeloplasty in Children: Comparative Analysis of Retrograde Endopyelotomy Versus Redo Pyeloplasty

Abstract
We compared retrograde endopyelotomy to redo pyeloplasty for the treatment of failed pyeloplasty in children. Of 32 patients with recurrent ureteropelvic junction obstruction retrograde endopyelotomy was performed in 18 and redo pyeloplasty was performed in 14. Patient age, gender, side, stent placement at initial pyeloplasty, presentation of secondary ureteropelvic junction obstruction, hospital stay, complications and success rates were compared. Success was defined as radiographic relief of obstruction as determined by ultrasound or diuretic renography at latest followup. Median patient age was 6 years (range 2 to 14) at retrograde endopyelotomy and 7.2 years (1 to 17) at redo pyeloplasty. Retrograde endopyelotomy technique consisted of holmium laser in 10 patients and cautery/balloon dilation in 8. Redo pyeloplasty was performed through a flank incision in 12 patients and by laparoscopy in 2. Retrograde endopyelotomy was successful in 39% of the patients, while redo pyeloplasty had a 100% success rate (p = 0.002). Of the patients with failed retrograde endopyelotomy 5 had a stricture greater than 1 cm and 7 were younger than 4 years. Mean length of the narrowed ureteral segment was 10.1 mm in the failed retrograde endopyelotomy group vs 5.8 mm in the successful group (p <0.01). Only 1 of 8 children (13%) had a successful retrograde endopyelotomy using cautery followed by balloon dilation. Hospital stay was 1.3 days for the retrograde endopyelotomy group and 2.9 days for the redo pyeloplasty group (p <0.01). Mean followup was 47 months (range 15 to 132) after retrograde endopyelotomy and 33.1 months (12 to 78) after redo pyeloplasty. Retrograde endopyelotomy had a significantly lower success rate than redo pyeloplasty for correction of recurrent ureteropelvic junction obstruction after failed pyeloplasty in children. Patient age less than 4 years and narrowed ureteral segment greater than 10 mm were associated with a poor outcome after retrograde endopyelotomy.