Nephrotoxicity from contrast material in renal insufficiency: ionic versus nonionic agents.

Controversy exists over whether use of low-osmolality contrast agents is of any benefit in mitigating the risk of contrast material-induced nephrotoxicity (CN) in patients with impaired renal function. To test this hypothesis, 101 adult inpatients with high serum creatinine levels (range, 1.4-2.4 mg/dL [120-210 mumol/L]) undergoing contrast material-enhanced computed tomography were randomized to receive ionic or nonionic (low-osmolality) contrast agents in a uniform dose. Changes in serum creatinine level at 48 hours were measured. Seven (14%) of the 50 patients receiving ionic contrast media experienced an increase of 25% or more in serum creatinine level. Only one (2%) of the 51 patients receiving nonionic contrast agents experienced such an increase, a statistically significant difference (P less than .05). In the subset of 25 diabetic patients, the difference was of a similar magnitude. These data suggest that ionic contrast media are more likely than nonionic contrast agents to cause mild exacerbation of renal insufficiency when given intravenously. However, there were no cases of clinically important CN in the study.