A Retrospective Review of Contrast Nephropathy in a General Population.

BACKGROUND One of the adverse events associated with administration of intravenous (IV) contrast media is contrast-induced nephropathy, yet its incidence is poorly characterized. We investigated the incidence of contrast-induced nephropathy in patients with elevated baseline serum creatinine concentrations who underwent computed tomography (CT) using IV contrast media. MATERIALS AND METHODS Using the electronic medical records at a community hospital, we retrospectively identified patients with elevated baseline serum creatinine concentrations who had undergone CT utilizing IV contrast media between January and July 2000, a period prior to the routine use of pretreatment as prophylaxis against contrast-induced nephropathy, and who subsequently developed elevated serum creatinine. We identified concomitant risk factors for the rise in serum creatinine in these patients aside from IV contrast media exposure. RESULTS One hundred ninety-three patients with a baseline serum creatinine concentration greater than 1.2 mg/dL underwent 236 CT studies utilizing IV low-osmolar contrast media. Nine of the 193 patients had a rise in serum creatinine ≥ 0.5 mg/dL up to 1 month later. None of these 9 patients had contrast exposure as the only risk factor for their rise in serum creatinine. CONCLUSION The role of IV contrast media in causing contrast-induced nephropathy and, thus, acute kidney injury, may be overestimated. Further study needs to be done into whether contrast-induced nephropathy is truly a common or even a real entity in patients receiving IV contrast media for routine studies who have no other risk factors for kidney injury warranting the expense, risks, and inconvenience of pretreatment.