A Calderazzi

Glomerular and tubular effects of contrast media diatrizoate and iopromide

The aim of this study is to evaluate the nephrotoxicity of two contrast media (CM), with different physicochemical characteristics: diatrizoate (ionic high-osmolar), iopromide (nonionic low-osmolar). Intravenous urography was performed in 34 patients: 17 were examined with diatrizoate and 17 with iopromide, randomly assigned. Different parameters of glomerular and tubular function were measured before and at 6, 24, and 48 h after urography. Both contrast media induced a reversible increase of urine enzymes, which was significantly higher after diatrizoate. In particular, diatrizoate determined a relevant increase of brush border enzymes gamma-glutamyltransferase (GGT) and alkaline phosphatase (ALP) and of cytosolic enzyme lactate dehydrogenase (LDH), while, after iopromide increases of urinary enzymes were less evident and were significant only for GGT and ALP. In addition, diatrizoate affected other tubular functions (clearances of phosphorus and uric acid) and slightly decreased glomerular function in a few patients. In no case did these glomerular and tubular effects have a clinical relevance. In conclusion, the nonionic low-osmolar contrast medium iopromide appeared less nephrotoxic than diatrizoate. The cost-benefit ratio needs further examination.

EFFECTS ON RENAL HEMODYNAMICS AND TUBULAR FUNCTION OF THE CONTRAST MEDIUM IOHEXOL IN RENAL PATIENTS

Renal function was assessed in 20 (11 female and 9 male, age 21-76 years, mean 53) renal patients with a creatinine clearance 25-145 ml/min, mean 95, to evaluate the effects of iohexol, a non-ionic low-osmolar contrast medium. Intravenous urography was performed in 16 patients and computed body tomography in 4, using a dose of iohexol ranged between 0.6-3.3 (mean 1.17) g/kg b.w. Different parameters of renal function were determined in the week preceding and 1, 3 and 5 days after the administration of iohexol. The principal renal effect of iohexol was an increase of urinary alanine aminopeptidase, gamma-glutamyltransferase, lactate dehydrogenase, alkaline phosphatase and N-acetyl-beta-D-glucosaminidase. The maximum increase of enzymuria was observed on day 1 after the administration of iohexol. In most cases enzymes returned to base-line values within 3 days. No relevant variation of renal hemodynamics (glomerular filtration rate and effective renal plasma flow) was observed after iohexol. In conclusion, iohexol can increase of urinary enzymes, but the effect is rapidly reversible and is not accompanied by a clinically significant impairment of renal hemodynamics.

Effects of Contrast Media on Renal Hemodynamics and Tubular Function: Comparison between Diatrizoate and Iopamidol

The administration of iodinated radiologic contrast media (CM) is the third cause of acute renal failure: about 12% of the cases in hospitalized patients (1,2).

Renal Effects of Ionic and Nonionic Contrast Media: Comparison between Diatrizoate Meglumine and Iopamidol

Renal damage is a potential adverse side effect of the administration of iodinated contrast media (CM). Infact, CM represent one of the most frequent causes of renal failure (1,2). The renal damage determined by CM is sometimes irreversible (3). The mechanisms of this renal injury are not yet well understood. Hyperosmolality of the administered CM has been claimed to be an important factor of renal damage (4). No exhaustive data are available concerning the effects on renal function and nephrotoxicity of the different CM available. The aim of this study is the comparative evaluation of renal effects and nephrotoxicity of two different CM: diatrizoate meglumine (a high-osmolality ionic CM) and iopamidol (a new low-osmolality nonionic agent), after intravenous administration.

Indications for Rapid Sequence Urography after Washout (Reinjection) in the Diagnosis of Renovascular Hypertension

38 hypertensive patients suspected of renovascular hypertension were examined with rapid sequence urography, washout, aortography or selective renal arteriography. When discordant results were found between rapid sequence urography and washout, we used a particularly helpful procedure which we define reinjection or rapid sequence urography after washout: washout is followed by the injection of a second 50-cm3 dose of contrast agent and five more roentgenograms at 1-min intervals. In our series, reinjection allowed correct diagnosis in 66% of the cases with discordant results and confirmed diagnosis in 83% of the cases of renovascular hypertension.