Predictive factors for contralateral reflux in patients with conservatively treated unilateral vesicoureteral reflux

Abstract

Purpose: We evaluated the rate of new contralateral reflux in children with conservatively treated vesicoureteral reflux, and identified predictive factors that could influence the appearance of contralateral reflux after a diagnosis of unilateral reflux on the first voiding cystourethrogram. Materials and Methods: We retrospectively evaluated 167 children who had been diagnosed with unilateral vesicoureteral reflux on the first voiding cystourethrogram. Patients with bilateral or secondary vesicoureteral reflux and those who had undergone only 1 voiding cystourethrography were excluded from the study. A total of 134 girls and 33 boys were analyzed. Average patient age was 55 months (range 2 to 169). All children had undergone at least 2 voiding cystourethrograms. A total of 84 patients underwent 3 voiding cystourethrograms, 35 underwent 4, 18 underwent 5, 9 underwent 6 and 3 underwent 7. Results: New contralateral reflux was evident on subsequent voiding cystourethrography in 35 patients (21%). Analysis of the presence of new contralateral reflux according to gender, reflux grade, age, side of reflux and bladder function (with or without lower urinary tract dysfunction) revealed that only medium or high grade reflux was a risk factor for new contralateral reflux. In 98 children (59%) vesicoureteral reflux resolved spontaneously. Of these patients 13 had new contralateral reflux and 85 did not (p = 0.017). Conclusions: We identified a 21% incidence of new contralateral reflux in patients with unilateral reflux after the first voiding cystourethrography who were treated conservatively. The main risk factor for contralateral reflux was the presence of medium or high grade reflux. Patients with new contralateral reflux had a lower rate of cure than those without development of contralateral reflux.