—We are in basic agreement with the letter of Levitz and Friedman. Our article has shown a low incidence of contrast-induced acute renal failure in diabetics both with and without preexisting renal insufficiency. However, six diabetics in whom renal insufficiency was detected had only a mild elevation in their serum creatinine levels (average level, 1.6 mg/dL). As pointed out in our discussion, this may account for the differences between our results and those reported by Harkonen and Kjellstrand.1 In a similar manner, the patient here had a serum creatinine level of 3.8 mg/dL before the contrast study, a level of renal function well below those of the group of diabetics with renal insufficiency described by us.
We also agree that measures to ensure volume repletion and a high urine flow, eg, sodium chloride irrigation or mannitol therapy, may not prevent contrast media—induced renal failure. This is highlighted by