Sysmex XN-9000全自动血液分析流水线复检规则的评估和验证

Validation of the review rules for Sysmex XN-9000 blood analyzer assembly line

目的对Sysmex XN-9000全自动血液分析流水线用复检规则进行评估和验证,以提高检验报告质量和工作效率。方法选取门诊、住院及体检患者标本共684例,均采用XN-9000流水线和涂片法进行检测,人工镜检由2名工作人员采用双盲法完成。对现有复检规则进行验证,并对结果进行分析。结果“Rerun”率为3.9%(27/684),“Reflex”率为7.6%(52/684),镜检率为21.5%(147/684);真阳性率为12.3%(84/684),假阴性率为2.5%(17/684),假阳性率为9.2%(63/684),真阴性率为76.0%(520/684),结果符合国际血液学复检专家组要求。人工镜检“红细胞大小不等”和“染色异常红细胞>30%”是造成假阴性的主要原因,以镜检结果“红细胞大小不等”为金标准,当RDW的截断(cut-off)值为16%时(ROC曲线下面积0.98,P<0.05),仪器法和镜检法高度一致,一致率为95.18%(灵敏度92.2%,特异度95.5%,Kappa值为0.76,P<0.001);以镜检结果“染色异常红细胞>30%”为金标准,当MCH的cut-off值为25 pg时(ROC曲线下面积0.92,P<0.05),仪器MCH结果与镜检法高度一致,一致率为96.78%(灵敏度73.6%,特异度98.7%,Kappa值0.76,P<0.001)。结论未设置与红细胞“红细胞大小不等”和“染色异常红细胞>30%”相关复检规则为实验室血液分析流水线复检规则的不足之处,但验证结果假阴性率小于5%表明该规则较为适用。若出现异常的报警信息或结果,应人工镜检复核,以免造成漏诊与误诊。

Objective Valuate and verify review rules of Sysmex XN-9000 automatic hematology analyzer for improving the quality and efficiency of reports.Methods A total of 684 samples of outpatients,inpatients and patients under physical examination were selected,analyzed and automatically smeared then stained by Sysmex XN-9000 automatic hematology analyzer.Two staff members verified the review rules and analysis result through blinded-review.Results The overall results met the requirements,with rerun rates 3.9%(27/684),"Reflex"rates 7.6%(52/684),and manual peripheral blood smear review rates 21.5%(147/684),of which the true positive rate was 12.3%(84/684),false negative rate was 2.5%(17/684),false positive rates 9.2%(63/684),true negative rates 76.0%(520/684).The main causes contributing to false negative were"anisocytosis"and"hypochromic cells>30%".Setting"anisocytosis"as the gold standard,when the cut-off value of RDW was 16%(the area under the ROC curve was 0.98,P<0.05),results from the MCH machine and microscopiy were highly consistent,reaching as high as 95.18%(sensitivity 92.2%,specificity 95.5%,Kappa value of 0.76,P<0.001).Setting"hypochromic cells">30%"as the gold standard,when the cut-off value of MCH was 25 pg(the area under ROC curve was 0.92,P<0.05),results from the MCH machine and microscopiy were highly consistent,reaching as high as 96.78%(sensitivity 73.6%,specificity 98.7%,Kappa value 0.76,P<0.001).Conclusion The results of false negative rate below 5%indicates that the existent retesting rules are practical,yet,limited without retesting based on"anisocytosis"and"hypochromic cells>30%".Abnormal flags or results should undergo manual microscopy in case of missed diagnosis and misdiagnosis.