Evaluation of the Sysmex XQ-320 three-part differential haematology analyser and its flagging capabilities.

BACKGROUND: Three-part differential (3PD) haematology analysers offer a quick, easy-to-use and economical way to acquire important information about a patient's physiology. In this study, we evaluated a new 3PD analyser, the Sysmex XQ-320, investigated its comparability with its predecessor (Sysmex XP-300) and the five-part differential analyser Sysmex XN-9000, and explored its flagging potential. METHODS: Analytical performance studies were conducted for repeatability, within-laboratory precision, between-day precision, carry-over and linearity with fresh blood and QC material. Method comparison was performed in 493 samples comparing XQ-320 with XP-300, using the XN-9000 as the gold standard. RESULTS: The XQ-320 excelled manufacturer's specifications in the analytical performance studies, except for MXD in within-laboratory and between-day precisions using the QC material level 1. The XQ-320 showed correlation values greater than 0.94 with XN-9000 for the majority of the 20 reportable parameters (MXD# 0.891, MXD% 0.898 and MCHC 0.849). Improvements over the XP-300 were observed in WBC in the leucocytopenic range (bias -0.038 vs. -0.097) and PLT (bias 2.568 vs. -7.877, intercept 3.880 vs. -8.845). Concordance between XQ-320 and XP-300 was 91.9% for the WBC histogram abnormal distribution flag and 95.3% for the PLT flag. Patterns of increased neutrophils and decreased mixed cells on the XQ-320 were observed in samples that raised a flag on XN-9000. CONCLUSION: The XQ-320 showed excellent analytical performance, and very good to excellent correlation with XN-9000 with improvements over XP-300. Flagging combined with parameter patterns identified additional suspected abnormal samples, thus making the XQ-320 an excellent solution for laboratories utilising 3PD analysers.

Comparison of ROTEM Sigma to Standard Laboratory Tests and Development of an Algorithm for the Management of Coagulopathic Bleeding in a Tertiary Center.

OBJECTIVE: The ROTEM sigma whole blood viscoelastic test uses different technology than the former delta model. Existing ROTEM based algorithms use cutoff values based on the delta model, and cannot be applied to the sigma model. The authors tested sensitivity and specificity of ROTEM sigma parameters to detect specific hemostatic deficiencies and established cutoff values with the aim of developing a treatment algorithm. DESIGN: Prospective observational evaluation of diagnostic accuracy. SETTING: This study was performed in a tertiary center. PARTICIPANTS: Blood samples for standard laboratory tests (SLTs) and ROTEM sigma analysis were obtained from 14 healthy volunteers and 35 patients showing various hemostatic disorders (isolated factor deficiencies, von Willebrand's disease, thrombocytopenia, hypofibrinogenemia, hyperfibrinogenemia, and patients undergoing cardiac surgery). INTERVENTION: Correlation coefficients were calculated between SLTs and ROTEM parameters in the extrinsic pathway activation, intrinsic pathway activation, and extrinsic pathway activation with platelet inhibition tests. Receiver operator characteristics defined the values of ROTEM parameters, which best predict plasma fibrinogen level measured by Clauss method <1.5 g/L and <2.0 g/L, platelet < 50 × 109/L and < 100 × 109/L, prothrombin time (PT) <80% and activated partial thromboplastin time (aPTT) >37 seconds and 1.5 times the upper normal limit. MEASUREMENT AND MAIN RESULTS: The combination of FIBTEM A5 ≤12 mm and EXTEM A5 ≤44 mm identified a fibrinogen level <1.5 g/L with 100% sensitivity and 77.5% specificity. PLTEM describes the platelet contribution to clot firmness and is calculated as EXTEM - FIBTEM. PLTEM A5 ≤16 mm sensitivity and specificity were 100% and 96.4% for a platelet count < 50 × 109/L. EXTEM coagulation time (CT) >80 seconds had a 25.0% sensitivity and a 100% specificity for a PT <80%. The INTEM CT >204 seconds showed a sensitivity of 75.0% and a specificity of 97.4% for an aPTT >37 and a sensitivity of 100% and a specificity of 80.0% for an aPTT >55 seconds. CONCLUSION: The authors present the first ROTEM sigma-based algorithm for the treatment of coagulopathic bleeding. The algorithm uses parameters with optimal sensitivity and specificity for critical values of SLTs determined from a heterogenous group of donors.