Intravenous urography in neonates and infants. What dose of contrast should be used?

The dose of contrast to be used for IV urography in neonates and infants is discussed. Toxic levels are only just above the currently accepted doses of 2-4.4 ml contrast medium per kg bodyweight. The dangers of expressing the dose of contrast medium as a volume of contrast related to the patient's age are discussed. A case is presented who had a severe reaction following an acceptable dose expressed as volume for age, but probably excessive when expressed as ml per kg bodyweight. It is concluded that for IV urography in neonates and infants the dose of contrast must be related to weight of patient and not its age; no dehydration should be used; and the injection should be slow, taking about three minutes.