Failure of subureteral bovine collagen injection for the endoscopic treatment of primary vesicoureteral reflux in long-term follow-up

Objectives. To evaluate the long-term efficacy of subureteral glutaraldehyd e cross-linked collagen injection (GAX 35) for endoscopic treatment of prim ary vesicoureteral reflux (VUR). Methods. We prospectively studied 36 patients (58 ureteral renal units), 30 girls and 6 boys with a median age of 6 years (range 2 months to 18 years) . All patients had primary VUR and were treated with a single subureteral c ollagen injection (GAX 35). The patients were followed up by voiding cystog raphy. Results. According to the International Reflux Study Classification, we fou nd the following reflux grades preoperatively: grade 1, 2 ureteral units; g rade II, 21 units; grade III, 28 units; grade IV, 4 units, and grade V, 3 u nits. All patients were treated with subureteral bovine collagen injection (GAX 35, mean volume 1.7 mL, range 0.7 to 3.5). All but 3 cases of reflux r esolved initially. The mean follow-up was 13 months (range 1 to 108). After 37 months of follow-up, only 5 (9%) of 57 treated units remained reflux fr ee. One unit was followed up for 17 months and also remained reflux free. Conclusions. These data suggest that a single endoscopic subureteral collag en injection is not effective in the long-term follow-up of patients with p rimary VUR. In the future, it will be important to determine whether the ne w, currently used, and soon be approved bulking agents show better long-ter m clinical results to prevent VUR recurrence than bovine collagen does. URO LOGY 55: 759-763, 2000. (C) 2000, Elsevier Science Inc.