Imaging of urinary tract malformations: intravenous urography and/or kidney ultrasonography?

We performed both kidney ultrasonography (KUS) and intravenous urography (IVU) in 56 children with urinary tract infections (UTI) to compare the effectiveness of these procedures in detecting urinary tract malformations (UTMs). In 7 patients where KUS findings were interpreted as normal, IVU detected the following UTMs: hydronephrosis (3), stenosis of the pelvi-ureteric junction (2), pelvi-ureteric duplication (1) and kidney dislocation (1). In 2 other patients, mild hydronephrosis diagnosed by KUS was not confirmed by IVU. With respect to IVU, KUS revealed a sensitivity of 77.4% and a specificity of 92%. In our experience, IVU is still irreplaceable in the diagnostic protocol of UTMs in children; KUS should be regarded as a useful complementary procedure.