Impact of Contrast Media on Estimated Glomerular Filtration Rate in Patients Undergoing CT Imaging

Abstract

Introduction: Although iodinated contrast media are commonly usedto enhance the diagnostic accuracy of computed tomography (CT), there are still concerns that they may lead to acute renal impairment, which isespecially evident in decreases in estimated glomerular filtration rate (eGFR). There is still conflicting evidence regarding renal effects in patientswith normal baseline kidney function. The short-term effects ofintravenous iodinated contrast on eGFR in a general CT-referred population. Population are evaluated in this study. METHODS: 52 patients (59.6%) female; mean age 52.57 ± 13.34 years) undergoing contrast-enhancedCT scans were performed as part of a prospective observational study. Values were measured before the administration of contrast and again 48hours later. To assess changes in renal function, correlation analysesPaired samples t-tests were used. RESULTS: Prior to contrast exposure, the mean eGFR was 84.29 ± 16.71 mL/min/1.73 m²; after contrast exposure, it significantly dropped to 77.62 ± 17.85 mL/min/1.73 m² (mean reduction 6.67 ± 4.36 mL/min/1.73 m²; t = 11.026; p < 0.001). Pre- and post-contrast eGFR values showed a perfect positive correlation (r = 0.970; p < 0.001), demonstrating that renal function samples were consistent among individuals. In patients with usual baseline renal status, the decreasedeGFR remained small and clinically mild despite being statistically meaningful. CONCLUSION: There is a detectable but slight short-term reduction in eGFR following the administration of iodinated contrast during CT imaging. These changes are indicative of temporary renal stress rather than clinically significant nephrotoxicity in individuals without prior renal impairment. The results highlight the need for ongoing attention and hydration-based precautions in vulnerable groupswhile supporting the general safety of contemporary contrast agents in low-risk populations.

Keywords: CT Scan, Contrast-Induced Nephropathy, Iodinated Contrast Media, eGFR, Renal Function, Kidney Safety