Renal sonography is not a reliable screening examination for vesicoureteral reflux

A retrospective analysis of 493 infants and children was performed to determine the reliability of renal sonography for identifying vesicoureteral reflux. Sonography was done in all cases within 8 hours of a voiding cystourethrogram. Vesicoureteral reflux was documented in 272 of 986 kidneys on voiding cystourethrography and there were 201 refluxing kidneys with normal ultrasound (25 with grade I reflux, 119 with grade II, 50 with grade III, 6 with grade IV and 1 with grade V). In 71 of the refluxing kidneys the ultrasound was abnormal due to pelvicaliceal dilatation in 45, a duplication anomaly in 6 and renal fossae abnormality in 20. Of the kidneys with vesicoureteral reflux 74% were sonographically normal. Sonography was not sufficiently sensitive or specific for detecting vesicoureteral reflux, since 28% of the missed refluxing kidneys had grade III or higher reflux.