McDonald Jennifer S, Day Patrick L, Spears Grant M, Bornhorst Joshua A, McDonald Robert J, Jannetto Paul J
From the Department of Radiology, Mayo Clinic, Rochester, MN (J.S.M., R.J.M.); Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN (P.L.D., J.A.B., P.J.J.); and Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN (G.M.S.).
Invest Radiol. 2025 Feb 24. doi: 10.1097/RLI.0000000000001165.
Gadolinium-based contrast agents (GBCAs) increase the sensitivity and clinical utility of magnetic resonance imaging (MRI) examinations and are used extensively worldwide. While concerns remain regarding the potential toxicity of retained gadolinium (Gd) based on "elevated" serum or urinary Gd concentrations, current Gd reference intervals were established in GBCA-naive patients with normal renal function. Therefore, the aim of this study was to determine the serum and urine Gd clearance in patients with normal renal function after being administered intravenous gadobutrol for a contrast-enhanced MRI examination.
Patients with normal renal function (estimated glomerular filtration rate ≥60 mL/min) with no prior GBCA exposure in the past 6 months were enrolled and had blood and urine collected before and ~1, 3, 7, 14, 28, 56, and 84 days after their gadobutrol-enhanced MRI examination to measure Gd at each time point. Serum and urine Gd were quantified using a clinically validated inductively coupled plasma mass spectrometry-based assay with a limit of quantitation of 0.1 ng/mL (μg/L).
Thirty-one patients who underwent a gadobutrol-enhanced MRI were enrolled, and 24 completed all collection time points. The pharmacokinetic data suggested a multicompartment (5 phase) model of elimination where 95% of patient's serum Gd fell below the unexposed reference interval (<0.5 ng/mL) at ~56 days and 95% of urine Gd would fall below the unexposed reference interval (<0.8 μg/g creatinine) at ~132 days. Based on review of the electronic medical record, none of the patients self-reported any Gd-related toxicity.
Current reference intervals for serum and urinary gadolinium clearance are not applicable for patients in the 5 months following intravenous gadobutrol exposure.
钆基造影剂（GBCAs）提高了磁共振成像（MRI）检查的敏感性和临床实用性，在全球范围内被广泛使用。尽管基于血清或尿液中钆（Gd）浓度“升高”，人们对体内残留钆的潜在毒性仍存在担忧，但目前的钆参考区间是在肾功能正常且未接触过GBCA的患者中确定的。因此，本研究的目的是确定肾功能正常的患者在静脉注射钆布醇进行增强MRI检查后血清和尿液中钆的清除情况。
纳入过去6个月内未接触过GBCA且肾功能正常（估计肾小球滤过率≥60 mL/min）的患者，在钆布醇增强MRI检查前以及检查后约1、3、7、14、28、56和84天采集血液和尿液，以测量各时间点的钆含量。血清和尿液中的钆采用经临床验证的电感耦合等离子体质谱法进行定量，定量限为0.1 ng/mL（μg/L）。
31例接受钆布醇增强MRI检查的患者入组，24例完成了所有采集时间点的检查。药代动力学数据提示存在一个多室（5相）消除模型，约56天时95%患者的血清钆低于未接触参考区间（<0.5 ng/mL），约132天时95%患者的尿液钆低于未接触参考区间（<0.8 μg/g肌酐）。根据电子病历回顾，没有患者自述任何与钆相关的毒性反应。
目前血清和尿液钆清除的参考区间不适用于静脉注射钆布醇后5个月内的患者。
