RESUMEN
PURPOSE: The development of contralateral reflux after successful unilateral antireflux surgery has led to controversy regarding etiology. Our aim was to analyze the incidence of newly developed contralateral reflux after successful unilateral Cohen's reimplantation in patients with grade III and IV reflux and to explain the postoperative trigonal distortion responsible for new contralateral reflux with case-control study. MATERIALS AND METHODS: We compared the incidence and outcome of contralateral reflux between the medical group with prophylactic antibiotics and the surgical group with unilateral Cohen's reimplantation in patients with unilateral vesicoureteral reflux. We retrospectively reviewed the records of 84 children seen in a 17-year period who had grade III (48 patients) and IV (36 patients) primary unilateral vesicoureteral reflux. Unilateral Cohen's reimplantation was done in 48 patients and prophylactic chemotherapy was done in 36 patients. RESULTS: Overall contralateral reflux developed in 13.8% of patients who underwent medical treatment and 14.6% of patients who underwent unilateral Cohen's reimplantation. In patients with grade III reflux, 13% of patients with medical treatment and 12% of patients with unilateral Cohen's reimplantation had contralateral reflux. Twelve patients with contralateral reflux had grade I (7 patients) and grade II (5 patients) reflux and resolved spontaneously within 18.2 months. CONCLUSIONS: The likelihood of trigonal distortion as the etiology of contralateral reflux is low given the similar incidence in cross-trigonal Cohen's reimplantation group and medical group with prophylactic chemotherapy in patients with grade III and IV primary vesicourerteral reflux.