An assessment of the "radioactive renogram" using O-iodohippurate sodium (Hippuran) labelled with radioactive iodine.

A "radioactive renogram" using o-iodohippurate sodium (Hippuran)-I(131) was performed in 57 patients who had either hypertension or various renal diseases. In longstanding essential hypertension, the initial uptake and secretory phases are often reduced below normal. In five hypertensive patients who were shown to have unilateral renal disease, the renogram showed significantly abnormal tracings on the affected side. In three patients suffering from ureteral obstruction, the excretory phase was significantly prolonged.On the basis of comparative albumin and iodohippurate renograms, the initial uptake can no longer be considered as a vascular phase, as previously believed.The iodohippurate-I(131) renogram is a useful adjunct in the investigation of hypertension and renal disease, providing information about each kidney not so readily obtained by other means. Nevertheless, the test does not supplant any other investigative procedure and should not be depended upon as a screening procedure.