Urinary tract anomalies associated with high grade primary vesicoureteral reflux.

BACKGROUND: Few studies have evaluated the significance of associated urological anomalies in vesicoureteral reflux (VUR). The aim of our study was to determine the incidence of associated urological anomalies in patients with high grade VUR and to assess their impact on renal parenchymal scarring.
METHODS: We retrospectively reviewed the hospital records of 1,765 consecutive cases diagnosed with high grade VUR (Grade III-V) at our hospital between 1998 and 2010. The diagnosis of VUR was made by a voiding cystourethrogram (VCUG). Renal scarring was evaluated by dimercapto-succinic acid (DMSA) scintigraphy and classified into three groups: mild (focal defects in uptake between 40 and 45%), moderate (uptake of renal radionuclide between 20 and 40%), and severe (shrunken kidney with relative uptake <20%). All associated urological anomalies were diagnosed by ultrasound or VCUG or DMSA scan.
RESULTS: Associated urological anomalies were present in 229 (13%) children. There were 87 boys and 142 girls. Duplex kidney was the main associated anomaly occurring in 148 (64.6%) of the 229 patients. Other anomalies were: bladder diverticulum in 29, solitary kidney in 12, ureterocele in 13, hypospadiasis in 11, pelviureteric junction obstruction in 9, malrotated kidney in 3, horseshoe kidney in 2, crossed fused ectopia in 1 and renal cyst in 1. DMSA scan revealed renal scarring in 105 (47.7%) of the 220 children who had a DMSA scan. 75 (50.7%) children with duplex kidneys showed renal scarring.
CONCLUSION: Associated urological anomalies occur commonly in patients with high grade VUR. Our data shows that nearly half of the patients with VUR and associated urological anomalies have renal scarring. Early recognition and treatment of VUR patients with associated urological anomalies may decrease the risk of renal parenchymal damage.