Annals of Laboratory Medicine最新文献

Background: Ensuring reference material (RM) commutability is crucial for evaluating measurement traceability in order to standardize laboratory tests. However, commutability assessment is not routinely performed. We assessed whether RMs prepared following CLSI C37-A guidelines could be used without assessing commutability by evaluating their commutability for four lipid measurements using the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and CLSI EP14 protocols.

Methods: We analyzed total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in frozen sera from 20 individuals and 11 RMs, prepared by the Korea Disease Control and Prevention Agency-Laboratory Standardization Project (per CLSI C37-A), using six routine measurement procedures (MPs). Regression equations and 95% prediction intervals derived from single-donor sera were analyzed following CLSI EP14. The IFCC protocol was used to assess differences in inter-MP biases between RM and clinical samples. The effect of the TG concentration on commutability was evaluated by analyzing biases between MP results and reference procedure-assigned values.

Results: RMs were commutable for most MP pairs for TC and TG. Commutability for HDL-C and LDL-C varied across RMs, with RM10 and RM11 showing higher TG levels (2.38 and 2.95 mmol/L, respectively) and lower commutability. Increased bias percentages from assigned values were observed for RMs with higher TG levels.

Conclusions: RMs prepared per CLSI C37-A were commutable with most MP pairs for TC and TG. Elevated TG levels affected HDL-C and LDL-C commutability, highlighting the need to consider TG concentrations during RM preparation and assess commutability to standardize laboratory tests.

Background: Pooled platelet (PLT) production methods differ worldwide. In Europe, the buffy coat (BC) method is predominantly used, with four to eight BCs being pooled to produce single- or double-dose PLT products. The European Directorate for the Quality of Medicines & HealthCare (EDQM) blood guide and Austrian legislation define a therapeutic PLT unit as ≥ 2 × 10¹¹ PLTs/unit. We optimized the manufacturing steps to produce double-dose PLT products from six BCs, aiming to enhance production efficiency while maintaining product quality.

Methods: We stepwise optimized our protocol starting from five BCs (BC5) (N=107). First, we included an additional BC (BC6) (N=110). Second, we used a hematology analyzer (Sysmex XN-1000) equipped with blood bank mode, which is a novel software application for measuring PLT counts in PLT units (BC6+XN-1000) (N=106). Third, we optimized the blood cell separator (BCS) settings to produce higher-volume BCs (BC6+XN-1000+BCS) (N=107). Fourth, we adapted the centrifugation (BC6+XN-1000+BCS+CF) (N=197). All units were pathogen-inactivated using the INTERCEPT blood system (amotosalen/ultraviolet A).

Results: Each optimization step significantly increased the yield ( × 10¹¹/PLT concentrate) (P <0.001). The mean yield increased from 2.83 (SD 0.39) for BC5 to 4.81 (SD 0.58) for BC6+XN-1000+BCS+CF. The mean BC volume increased from 47.78 mL (SD 5.09) to 55.59 mL (SD 5.11) following BCS adaptions (P <0.001).

Conclusions: After stepwise protocol optimization, we could produce pathogen-inactivated double-dose PLT concentrates by pooling six BCs, complying with national regulations and EDQM quality requirements while reducing costs and minimizing blood wastage.