Radiocontrast-induced nephropathy: an update

Both diagnostic and therapeutic studies frequently utilize radiocontrast media to enhance images. As a result, use of these agents has increased markedly over the past decade with more than 10 million studies performed on a yearly basis in the United States. Development of acute kidney injury (AKI) is a common complication of radiocontrast exposure in patients who possess underlying risk factors. Impor-tantly, radiocontrast-induce nephropathy (RCIN) is associated with increased short- and long-term mortality. Thus, at risk patients should be identified prior to administration of radiocontrast to allow choice of other potential imaging options or employment of prophylactic interventions. Currently, use of isotonic intravenous fluids is the only proven beneficial preventive therapy. Use of low volumes of radiocontrast and avoidance of nephrotoxic medications are also accepted as nephroprotective. Mixed results exist on the utility of N-acetylcysteine (NAC) therapy and low versus iso-osmolar radiocontrast agents in preventing RCIN. While hemodialysis appears to have no beneficial role, a single center's experience with hemofiltration is associated with a reduction in RCIN and other clinical endpoints. Several therapies have no role in the prevention of RCIN and should be avoided. This review will provide an up to date examination of the current status of these issues as they relate to RCIN.