Clearances of Inulin and Para-Aminohippurate before and after Urography Using High Dosage of Contrast Medium in Patients with Renal Insufficiency

Renal function, as estimated from clearances of inulin and para-aminohippuric acid (PAH), was studied in six patients before and after urography with large doses of a metrizoate contrast medium. All six patients had chronic pyelonephritis and marked renal impairment, the average clearance of inulin and of PAH being 22 and 87 ml/min/1.732 BSA, respectively. The clearances of inulin and PAH were unchanged after urography. There was, then, no evidence of any worsening of the pre-existent kidney damage. Urography was diagnostic in five of the six cases.