Impact of contrast agents on renal function: A systematic review

Background: Radiological contrast agents are essential for obtaining accurate medical images; however, their use carries a significant risk of nephrotoxicity, a complication that can lead to acute kidney injury (AKI). This systematic review aims to assess the impact of iodinated and gadolinium-based contrast agents on kidney function, comparing their relative risk of inducing contrast-induced nephropathy (CIN). Objectives: To evaluate the impact of radiological contrast agents on renal function. Material and methods: A systematic review of the literature available in databases such as PubMed and Google Scholar were conducted. Observational studies controlled clinical trials, meta-analyses, and systematic reviews published between 2009 and 2024 that evaluated the impact of iodinated and gadolinium-based contrast agents in adult patients undergoing imaging studies were included. Results: The review indicated that the incidence of contrast-induced nephropathy (CIN) varies according to the type of contrast agent and patient conditions. In populations without risk factors, the incidence of CIN was low, while in patients with chronic kidney disease or diabetes, the incidence was significantly higher (up to 12%). No significant differences were observed between iodinated and gadolinium-based contrast agents in terms of CIN risk. In patients with renal insufficiency, proper hydration, combined with other measures such as the use of nitrates, was highlighted as the most effective preventive strategy. There was no clear benefit of N-acetylcysteine in reducing CIN. Overall, intravenous hydration remains the key preventive measure to reduce CIN risk. Conclusion: The literature review indicates the need for more rigorous clinical trials to assess the efficacy and safety of different contrast agents. It highlights the importance of a thorough assessment of individual risk factors to minimize nephrotoxicity in patients undergoing contrast-based procedures.