Component Development Laboratory, NHS Blood and Transplant, Cambridge, UK.
Clinical Services, NHS Blood and Transplant, UK.
Transfusion. 2021 Feb;61(2):568-578. doi: 10.1111/trf.16196. Epub 2020 Nov 17.
Manufacture of platelet concentrates (PCs) and plasma may fail to remove all residual red blood cells (rRBCs). Measuring rRBCs for compliance to guidelines has proven challenging, leading to an absence of a consensus methodology. Sysmex hematology analyzers with the Blood Bank mode (BB mode) analysis option offer the potential for automated rRBC counting. We therefore performed a two-site appraisal of the system.
Performance characteristics were determined using platelet and plasma samples spiked with RBCs. Sample stability (n = 47) and the impact of sample type were also assessed. Components (platelets, n = 1474; plasma, n = 77) prepared using different routine manufacturing methods were tested to assess variation in rRBC concentration.
Linearity studies up to 19 000 RBCs/μL demonstrated good correlation between expected and observed results (R ≥ 0.9731), and flow cytometric results also correlated well with BB mode (R = 0.9400). Precision analysis gave a limit of quantitation of 6 to 7 RBCs/μL, and carryover was 0.03%. Ethylenediaminetetraacetic acid and plain tube results were not significantly different (P ≥ 0.10), and samples were stable up to 24 hours. Apheresis PCs produced at two sites had lower rRBC concentrations (medians, 17 and 13 RBCs/μL) than those produced with the buffy coat method either manually (median, 681 RBCs/μL) or with the automated Terumo Automated Centrifuge and Separator Integration process (median, 81 RBCs/μL). All PCs failing visual inspection as having RBCs ≥4000 RBCs/μL were also detected by the BB mode.
The BB mode had acceptable performance characteristics and has the potential for integration into a fully automated process control system for rRBC enumeration in plasma and PCs.
血小板浓缩物 (PCs) 和血浆的制备可能无法去除所有残留的红细胞 (rRBC)。为了符合指南的要求，rRBC 的测量一直具有挑战性，导致缺乏共识方法。具有血液库模式 (BB 模式) 分析选项的希森美康血液学分析仪具有自动 rRBC 计数的潜力。因此，我们对该系统进行了两次现场评估。
使用添加 RBC 的血小板和血浆样本确定性能特征。还评估了样品稳定性 (n = 47) 和样品类型的影响。使用不同常规制造方法制备的成分 (血小板，n = 1474；血浆，n = 77) 进行测试，以评估 rRBC 浓度的变化。
线性研究高达 19000 RBC/μL，显示预期结果与观察结果之间具有良好的相关性 (R ≥ 0.9731)，并且流式细胞术结果也与 BB 模式很好地相关 (R = 0.9400)。精密度分析得出定量下限为 6 到 7 RBC/μL，且携带为 0.03%。乙二胺四乙酸和普通管结果无显著差异 (P ≥ 0.10)，样品在 24 小时内稳定。在两个地点生产的单采 PCs 的 rRBC 浓度较低 (中位数，17 和 13 RBC/μL)，低于手工制备的富细胞层法 (中位数，681 RBC/μL) 或使用自动化 Terumo 自动离心机和分离器集成过程 (中位数，81 RBC/μL)。所有通过肉眼观察发现 RBC≥4000 RBC/μL 的 PCs 也被 BB 模式检测到。
BB 模式具有可接受的性能特征，并且有可能集成到用于血浆和 PCs 中 rRBC 计数的全自动过程控制系统中。
