Prediction of vesico-ureteral reflux in children from intravenous urography films.

Intravenous urography and voiding urethrocystography were performed on 255 children with urinary tract infection. Eighty-six (34%) of these children had some kind of abnormality of the urinary tract. Vesico-ureteral reflux was observed to 96 ureters (19%) in 69 children (27%). The prediction of vesico-ureteral reflux by two radiologists from urography films only gave 46 (48%) and 51 (53%) false negative results respectively. In cases of clinically important reflux (III--V degrees), however, the rate of false negative predictions was 0/18 and 1/18 (6%) respectively. The rate for false positive predictions were 45/413 (11%) for both radiologists. In view of the number of pathological findings in this series i.v. urography is recommended as a routine in children undergoing urological work-up after their first urinary tract infection. As the clinically important vesico-ureteral reflux seems to be predictable from urography films alone, voiding urethrocystography seems not to be justified in children with negative i.v. urography, and can be postponed and carried out later if the urinary tract infection recurs.