Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium.
Department of Pharmacy, Ghent University Hospital, Corneel Heymanslaan 10, Ghent, Belgium; Heymans Institute of Pharmacology, Ghent University, Corneel Heymanslaan 10, Ghent, Belgium; Department of Paediatric Intensive Care, Ghent University Hospital, Corneel Heymanslaan 10, Ghent, Belgium.
J Chromatogr B Analyt Technol Biomed Life Sci. 2021 May 1;1171:122623. doi: 10.1016/j.jchromb.2021.122623. Epub 2021 Mar 4.
The glomerular filtration rate (GFR) is considered the best overall index for the renal function. Currently, one of the most promising exogenous markers for GFR assessment is iohexol. In this study, the suitability of volumetric absorptive microsampling (VAMS) as alternative for the conventional blood sampling and quantification of iohexol in paediatric plasma was assessed. Therefore, a new, fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed. Subsequently, the clinical suitability was evaluated in 20 paediatric patients by comparing plasma iohexol concentrations and associated GFR values obtained by the VAMS method with those obtained by conventional blood sampling and quantification of iohexol in plasma. The developed, simple and cost-effective LC-MS/MS-method fulfilled all pre-set validation acceptance criteria. Iohexol could be accurately quantified within a haematocrit range of 20-60% and long-term stability of iohexol in VAMS was demonstrated up to 245 days under different storage temperatures. Both iohexol plasma concentrations (r = 0.98, mean bias: -4.20%) and derived GFR values (r = 0.99; mean bias: 1.31%), obtained by a conventional plasma and the VAMS method, demonstrated good correlation and acceptable bias. The agreement between the two methods was especially good for GFR values higher than 60 mL/min/1.73 m. Nevertheless, for GFR values <60 mL/min/1.73 m the accuracy compared to the plasma method was lower. However, small adjustments to the sampling protocol could probably solve this problem.
肾小球滤过率（GFR）被认为是肾功能的最佳整体指标。目前，用于评估 GFR 的最有前途的外源性标志物之一是碘海醇。在这项研究中，评估了体积吸收微采样（VAMS）作为替代传统采血和定量儿童血浆中碘海醇的方法的适用性。因此，开发了一种新的、完全验证的液相色谱-串联质谱（LC-MS/MS）方法。随后，通过将 VAMS 方法获得的血浆碘海醇浓度和相关 GFR 值与传统采血和定量血浆中碘海醇获得的 GFR 值进行比较，在 20 名儿科患者中评估了该方法的临床适用性。开发的、简单且具有成本效益的 LC-MS/MS 方法满足了所有预设的验证接受标准。在 20%至 60%的红细胞压积范围内，可以准确地定量碘海醇，并且在不同储存温度下，VAMS 中碘海醇的长期稳定性可长达 245 天。通过传统血浆和 VAMS 方法获得的碘海醇血浆浓度（r=0.98，平均偏差：-4.20%）和衍生的 GFR 值（r=0.99；平均偏差：1.31%）都显示出良好的相关性和可接受的偏差。两种方法之间的一致性特别好，适用于 GFR 值高于 60 mL/min/1.73 m 的情况。然而，对于 GFR 值低于 60 mL/min/1.73 m 的情况，与血浆方法相比，其准确性较低。但是，对采样方案进行小的调整可能会解决这个问题。
