Contrast-induced nephropathy: the wheel has turned 360 degrees

Contrast-induced nephropathy (CIN) has been a hot topic during the last 5 years due its association with increased morbidity and mortality. CIN is an important complication, particularly in patients with advanced chronic kidney disease (CKD) associated with diabetes mellitus. Methods to diminish the incidence of CIN have been highly contentious. They include choice of contrast, pharmacologic manipulation, and volume expansion. The pathophysiology of this complication remains uncertain, but reduction in renal blood flow and direct toxicity of tubular cells has been implicated. More than 900 publications under the heading CIN have been published during the last 5 years. Fewer than 5% of these publications are randomized prospective controlled studies. In spite of the large number of reports on CIN, very little has been changed. The use of the smallest possible dose of low- or iso-osmolar contrast media, volume expansion, stopping nephrotoxic drugs, and avoiding repeat contrast injections within 48 hours remain the most effective approach to reduce the risk of CIN.