Ischemia-Modified Albumin, Creatinine, an‎d Paraoxonase-1 Levels in Serum of Patients Undergoing Intravenous Contrast-Enhanced Computed Tomography and Its Association with Contrast-Induced Nephropathy

Background: Following contrast-enhanced computed tomography (CECT) contrast-induced nephropathy (CIN) may occur in patients with renal insufficiency or diabetes. Creatinine, the most common marker of CIN, may not be an accurate measure of damage and is affected by many non-renal factors. Our aim was to evaluate ischemia-modified albumin (IMA) as an early CIN marker and correlate it with paraoxonase-1 (PON-1) and creatinine before and after CECT. Methods:Forty-eight adult patients scheduled for intravenous CECT, regardless of indication or body region for CECT, were included in this prospective study. Venous blood samples were obtained 12-24 hours before and after contrast media (CM) administration. Ischemia-modified albumin and PON-1 were estimated using methods described by Bar-Or et al. and Dantoine et.al., respectively. Creatinine was estimated on an automated analyzer. Results:Significant differences in IMA (P < 0.001) and PON-1 (P < 0.001) levels were found between pre- and post-CECT samples, while the difference for creatinine was not significant (p = 0.073). No correlation was found between IMA and PON-1 or IMA and creatinine in either the pre- or post-CECT samples. Conclusions:After CM administration patients are subjected to oxidative stress and/or ischemia, as revealed by elevated IMA and decreased PON-1 levels; however, creatinine levels, most commonly estimated to assess reduced renal function, did not reflect the condition accurately. IMA may be a sensitive marker for CIN but further studies are required to confirm its usefulness.