CAMAG DBS Laboratory, Muttenz, Switzerland.
Ther Drug Monit. 2021 Jun 1;43(3):346-350. doi: 10.1097/FTD.0000000000000887.
The patient's hematocrit (HCT) level can adversely affect the analysis results when dried blood spots (DBS) are used for sampling. Volumetric DBS sampling has been proposed to nullify the impact of HCT area bias (spreading area) on DBS by normalizing to a known sample volume. However, this strategy ignores DBS-related parameters such as analyte properties (red blood cell-to-plasma ratio) and HCT recovery bias. With the recent release of fully automated HCT measurement systems for DBS analysis, a broad range of end users are now able to measure and correct a sample's HCT level in a nondestructive manner. These systems permit correction for all known HCT-related impacts on DBS, such as analyte properties, HCT recovery bias, HCT area bias, and venous blood-to-DBS ratio, supporting and accelerating future quantitative DBS applications. However, with these novel tools, new questions arise concerning the normalization of analytical results, the choice of technique (single-wavelength reflectance vs near-infrared spectroscopy), and the DBS card-handling process post sampling. Herein, the necessary considerations for end users are addressed and examples are provided.
当使用干血斑 (DBS) 进行采样时，患者的血细胞比容 (HCT) 水平可能会对分析结果产生不利影响。已经提出了体积 DBS 采样方法，通过将其归一化为已知的样品体积，来消除 HCT 面积偏差（扩散面积）对 DBS 的影响。然而，这种策略忽略了与 DBS 相关的参数，例如分析物特性（红细胞与血浆的比例）和 HCT 回收率偏差。随着最近用于 DBS 分析的全自动 HCT 测量系统的发布，现在越来越多的广泛的终端用户能够以非破坏性的方式测量和校正样本的 HCT 水平。这些系统允许对所有已知的与 HCT 相关的 DBS 影响进行校正，例如分析物特性、HCT 回收率偏差、HCT 面积偏差和静脉血与 DBS 的比例，支持和加速未来的定量 DBS 应用。然而，有了这些新工具，就出现了关于分析结果归一化、技术选择（单波长反射率与近红外光谱）以及采样后 DBS 卡处理过程的新问题。本文针对终端用户的必要考虑因素进行了讨论，并提供了示例。
