EDTA-K_2抗凝剂致血小板假性减少的原因及纠正方法探讨

Cause and correction of seudothrombocytopenia caused by anticoagulant EDTA-K_2

目的探讨乙二胺四乙酸二钾(EDTA-K2)抗凝剂对假性血小板减少(PTCP)的影响及纠正方法。方法对82例PTCP者用EDTA-K2、枸橼酸钠分别抗凝重新抽血送检,EDTA-K2抗凝管在15 min、1 h及2 h,枸橼酸钠抗管凝在15 min以内分别用血细胞分析仪检测,同时取末梢血人工显镜血小板计数。另设健康对照组20例分别用EDTA-K2、枸橼酸钠抗凝采静脉血,在0 min、5 min、15 min、30 min、60 min用血细胞分析仪计数血小板。结果 PTCP组EDTA-K2抗凝血15 min血小板计数结果明显低于枸橼酸钠抗凝和显微镜计数结果(P<0.001);1 h及以后更低。枸橼酸钠抗凝和显微镜计数结果比较,差异无统计学意义(t=1.646,P=0.103);对照组EDTA-K2抗凝结果和枸橼酸钠抗凝15 min以内计数结果比较差异无统计学意义(P>0.05),30 min及以后结果差异有统计学意义(P<0.001)。EDTA-K2抗凝标本0 min与60 min检测结果比较差异无统计意义(t=0.857,P=0.402)。PTCP组EDTA-K2抗凝标本血涂片可见大量血小聚集或卫星现象,随时间延长聚集加剧。结论 EDTA-K2对血小板可产生聚集作用,引起PTCP。在一定条件下,用枸橼酸钠替代EDTA-K2抗凝静脉血做血小板计数或采末梢血用草酸胺稀释液显微镜人工计数,可以纠正PTCP。

Objective To study the effect of anticoagulant ethylenediamine tetraacetic acid （EDTA）-K2 on pseudothrombocytopenia （PTCP）,and to investigate the correction methods.Methods Eighty-two PTCP cases used EDTA-K2,sodium citrate as anticoagulants and the blood samples were drawn for examination.EDTA-K2 anticoagulant tubes at 15 min,1 h and 2 h,sodium citrate anticoagulant tubes within 15 min were detected by automatic hematology analyzer.At the same time,the peripheral blood was taken,and the platelets were counted through microscope.Another 20 healthy people were selected as the control group,with EDTA-K2,sodium citrate anticoagulation,in which platelets were counted at 0 min,5 min,15 min,30 min,60 min by automatic hematology analyzer.Results The platelet count results of PTCP group with EDTA-K2 anticoagulation at15 minute was significantly lower than that of PTCP group with sodium citrate anticoagulation and microscopic counting （P〈0.001）,even lower at 1 h.The results of sodium citrate anticoagulation within 15 minutes had no statistically significant difference with that of microscopic counting （t=1.646,P=0.103）.The results of EDTA-K2 anticoagulation in the control group and sodium citrate anticoagulation within 15 minutes showed no statistically significant difference （P〉0.05）,with statistically significant difference at 30 min and later （P〈0.001）.EDTA-K2 anticoagulant specimens of 0 min and 60 min detection results has no statistically significant difference （t=0.857,P=0.402）.The blood smears of PTCP group with EDTA-K2 anticoagulation specimens showed large amounts of blood aggregation or satellite phenomenon,aggregation increased with the extension of time.Conclusion EDTA-K2 can induce aggregation of platelets and cause PTCP.Under certain conditions,the replacement of EDTA-K2 with sodium citrate for anticoagulation for platelets counting or artificial microscopic counting of peripheral blood with oxalic acid amine dilution,can correct PTCP.