RESUMO
PURPOSE: The management of vesicoureteral reflux (VUR) in a duplicated collecting system (DS) is controversial. Available literature is sparse and it does not assess all co-factors. We compared the outcome of VUR in DS cases with VUR in single system (SS) cases, given similar clinical management in the 2 groups. MATERIALS AND METHODS: A retrospective cohort study was done to compare the outcome of VUR in 35 children (44 units) with a DS and in 95 (150 units) with an SS. Patients with secondary reflux, incomplete duplication and ureterocele were excluded. Two groups were similar in terms of prognostic factors. Mean followup in the DS and SS groups was 43 and 48 months, respectively. Outcomes of interest were spontaneous resolution or uncomplicated persistence vs surgical correction. The same criteria were used to intervene surgically in the 2 groups. RESULTS: In the DS group 24 of 35 patients (69%) underwent surgery compared with 25 of 95 (25%) in the SS group. Multivariate analysis showed an association between surgery due to complications and the presence of DS (p = 0.0001). Higher grade and female gender were independent predictors (p = 0.02 and 0.0007, respectively). The likelihood of undergoing surgery was the same for low grade VUR (I and II) in the DS and SS groups (p = 0.16). No resolution was seen in the duplex group with severe VUR at a mean followup of 42 months. CONCLUSIONS: Low grade VUR in DS cases has an outcome similar to that of VUR in SS cases. Females with moderate or high grade VUR and a DS should be treated differently because they present more often with complications.