EDTA依赖性血小板假性减少6例

EDTA依赖性血小板减少是由于EDTA盐作为抗凝剂的抗凝血,在全血细胞分析仪检测时,由于血小板相互聚集而发生血小板计数减少的假象。ED-TA-K2是国际血液学标准委员会1993年推荐用作血细胞分析的抗凝剂,此抗凝剂以其抑制血小板的聚集、较好地保持血细胞形态而被ICSH认定,并得     

自制枸橼酸钠干粉抗凝管在EDTA依赖性假性血小板减少症中的应用研究

目的:制备最佳抗凝浓度的枸橼酸钠干粉抗凝管,使EDTA依赖性假性血小板减少症患者的血小板计数更加简便、准确。方法:1配置不同浓度枸橼酸钠干粉抗凝管,优选其最佳抗凝浓度、抗凝血量及检测时间范围。2使用不同抗凝管同时采集4种不同类型患者静脉血,进行血小板计数,对EDTA依赖性假性血小板减少症患者同时进行末稍血手工法血小板计数及抗凝血涂片染色观察血小板聚集情况。结果:1枸橼酸钠干粉抗凝管的最佳抗凝浓度为12.8mg/管,在抗凝血量200~800μl、上机检测时间10~120min的条件下计数血小板可得到较准确结果。2最佳抗凝浓度的枸橼酸钠干粉抗凝管在门诊体检者、血小板增多患者、真性血小板减少症患者中,血小板结果与EDTA-K2真空抗凝管血小板结果比较,差异无统计学意义;在EDTA依赖性假性血小板减少症患者中,血小板结果与末稍血手工法计数血小板结果比较,差异亦无统计学意义,枸橼酸钠干粉抗凝血涂片染色观察血小板呈单个散在分布。结论:自制的枸橼酸钠干粉抗凝管可简便、准确地纠正EDTA依赖性假性血小板减少症患者的血小板数量。     

血小板源生长因子β受体反义寡核苷酸对血小板源生长因子诱导大鼠血管平滑肌细胞迁移的影响

为研究血小板源生长因子β受体反义寡核苷酸对血小板源生长因子诱导的大鼠血管平滑肌细胞迁移的影响和作用机制，利用激光共聚集显微镜观察平滑肌细胞对异硫氰酸荧光素标记的反义寡核苷酸的摄取和细胞内定位，改良Boden's小室法观察平滑肌细胞迁移。结果发现，加入反义寡核苷酸培养24h及48h后荧光分别位于细胞浆内和细胞核内，5umol/L以上浓度反义寡核苷酸作用36h后，被血小板源生长因子诱导迁移通过Boyden's小室碳纤维素膜的细胞数量小于空白对照组；正义，错义寡核苷酸和5umol/L以下浓度反义寡核苷酸迁移抑制不明显，提示血小板源生长因子β受体反义寡核苷酸在细胞核内呈时间和浓度依赖性抑制血小板源生长因子诱导的血管平滑肌细胞迁移。     

调脂中药抗血小板聚集和对红细胞流变性影响的实验研究

目的 :收集文献报道具有调脂作用的中药 63种 ,观察其对血小板聚集和红细胞流变性的影响。方法 :63种中药体外孵育抗人血小板聚集实验 ,将其中作用显著进行大鼠灌胃实验 ,测定血小板聚集、红细胞聚集、变形等。结果 :5 1种体外抗血小板聚集作用明显 ,其中枳实等 11种作用优于或和阿斯匹林相当 ,该 11种中药大鼠灌胃均能明显抑制血小板聚集 ,其中 10种还能降低红细胞聚集。结论 :枳实、赤芍、大黄、黄连、银杏叶、山楂、徐长卿、茶叶、葛根、灵芝、陈皮抗血小板聚集作用优于或和阿斯匹林相当 ,除银杏叶外余 10种中药还能降低红细胞聚集 ,对红细胞变形、取向、松弛指数均无影响。     

乙二胺四乙酸依赖性假性血小板减少症1例

血细胞分析是检验科日常工作中的常规检验项目,乙二胺四乙酸（EDTA）作为血细胞分析抗凝已被ICSH认定,并广泛用于临床,EDTA有时会引起血小板聚集导致血小板在自动化仪器计数中出现假阳性降低的现象,即EDTA依赖性假性血小板假性减少。     

血红蛋白在三氧化二砷抑制血小板聚集中的功能研究

目的:检测血红蛋白与砷的结合,分析血红蛋白在三氧化二砷(ATO)抑制血小板聚集功能中发挥的作用。方法:电喷雾质谱(ESI-MS)检测血红蛋白与氨基氧化苯胂酸(PAPAO)的结合。在2 mg/L胶原或2μmol/L腺苷二磷酸(ADP)刺激下,比较经10μmol/L ATO处理后,富血小板血浆(PRP)和全血血小板聚集的差异。PRP中加入0、40、60、80、100、120 g/L的血红蛋白经10μmol/L的ATO处理后,检测血小板聚集。结果:血红蛋白β链可与一分子有机砷PAPAO结合,并脱去一分子水。ATO处理PRP以及全血,两者血小板聚集均受到显著抑制,但是对PRP血小板聚集的抑制更加明显。在刺激剂为2 mg/L胶原时,血红蛋白≥80 g/L可逆转ATO对血小板聚集的抑制,并且具有浓度依赖性(r=0.956,P=0.003);同样的,在刺激剂为2μmol/L ADP时,血红蛋白≥80 g/L可逆转ATO对血小板聚集的抑制(r=0.940,P=0.005)。结论:在体外血红蛋白通过与砷结合,能够削弱ATO对血小板聚集的抑制,并且具有浓度依赖性。血红蛋白在ATO抑制血小板聚集过程中发挥重要作用。     

抗血小板治疗

抗血小板药是一类能抑制血小板活化 ,进而阻止血小板参与血栓形成的药物 ,其在动脉血栓形成中的作用尤为突出 ,因而成为防栓、治栓的重要药物。1　传统抗血小板药物1.1　阿司匹林　基础研究表明 ,血小板在动脉粥样硬化斑块形成及动脉血栓形成中起关键作用。阿司匹林的作用机理是通过抑制环氧化酶 ,不可逆地阻断花生四烯酸至 TXA2 的途径 ,进而抑制血小板聚集。除了花生四烯酸途径之外 ,尚有 90余种途径可诱发血小板聚集 ,而阿司匹林仅为一种较弱的血小板抑制剂 ,大量临床试验均证实阿司匹林确能降低各种心血管疾病 (短暂心肌缺血、心肌梗…     

EDTA—K2抗凝剂引发血小板假性减少2例

EDTA—K2是国际血液学标准委员会（International Committee For Standardization in Hematology，ICSH）1993年推荐用作血液分析的抗凝剂，此抗凝剂可以抑制血小板的聚集，从而达到抗凝的目的，抗凝效果满意，已得到临床的广泛使用。但EDTA盐偶可引起血小板聚集，从而导致血细胞分析仪计数血小板时出现血小板假性减低的现象，     

API0134对高脂血症家兔血栓形成及血小板信号转导物质的影响

建立高脂血症家兔动脉血小板依赖性血栓模型，应用流式细胞术、放射免疫法及^3H-肌醇掺合等检测方法观察穿心莲成分API0134对闭塞性血栓形成时间、血小板聚集功能、血小板胞浆游离Ca^2 和Mg^2 浓度以及血小板内环磷酸腺苷、环磷酸鸟苷和三磷酸肌醇含量的影响。结果发现，API0134能够显著延长闭塞性血栓形成时间和抑制血小板聚集。50mg/kgAPI0134的药理作用明显强于5mg/kgAPI0134。API0134可显著抑制血栓形成所诱导的血小板内[Ca^2 ]I、[Mg^2 ]I和三磷酸肌醇浓度升高，显著抑制血小板内环磷酸腺苷浓度降低。抑制作用与用药剂量有关。结果提示，API0134具有较强的抗血栓形成和抗血小板聚集作用。抗血小板聚集的作用机制与调节血小板信号转导物质[Ca^2 ]I、[Mg^2 ]I、环磷酸腺苷和三磷酸肌醇的平衡有关。     

冠状动脉造影术后股动脉穿刺部位局部血肿并发假性血小板减少症1例

<正>目前临床一般常规使用乙二胺四乙酸盐(ethylenediami-netetraacetate,EDTA)作为血细胞计数的抗凝剂。但在实际应用中,常有EDTA会使部分标本发生血小板的聚集,导致血小板假性减少,即EDTA依赖性假性血小板减少症(ED-     

Flow cytometric analysis of platelet activation under calcium ion-chelating conditions

Platelet activation and aggregation results in factitious counting and sizing in routine haematology testing. In this study, the possibility of platelet activation in anticoagulated solutions was examined. Whole blood was examined using an automated counter and a flow cytometer before and after strong vortex agitation. Blood treated with ethylenediaminetetraacetic acid (EDTA) exhibited platelet activation both pre- and postagitation but activated platelets did not cause platelet aggregation. With sodium citrate, platelets were only minimally activated both pre- and postagitation. Heparin-treated blood exhibited minimal platelet activation preagitation, but agitation resulted in strong platelet activation and aggregation. Platelet size was increased by agitation in blood with EDTA and with sodium citrate, in association with significant increases in mean platelet volume (MPV) and platelet distribution width (PDW), but MPV and PDW were significantly higher in EDTA solution than in sodium citrate solution. Change in platelet size was observed even in the presence of EDTA, indicating that careful sampling and processing are needed in the collection of specimens. Specimens obtained from patients with EDTA-dependent pseudothrombocytopenia exhibited the same level of activation as controls, although platelets exhibited aggregation in such specimens. In conclusion, platelet activation involving platelet size change can occur in the absence of calcium ions in blood treated with EDTA.     

Transient pseudothrombocytopenia in a neonate: transmission of a maternal EDTA-dependent anticoagulant

EDTA-dependent pseudothrombocytopenia (PTCP) is characterised by a low platelet count caused by autoantibodies in the serum reacting with EDTA-anticoagulated blood. EDTA-dependent PTCP is caused by a factor that retains EDTA anticoagulation activity in the serum. We report here that a neonate from a mother with PTCP presented with transient low platelet counts when EDTA was used as an anticoagulant. To confirm the transmission of a maternal serum factor to the neonate, we examined to add the maternal serum into the normal blood. Platelet count decreased significantly after adding maternal serum. Clumped platelets were also observed in the smears of mixed samples.     

Transient pseudothrombocytopenia in a neonate: Transmission of a maternal EDTA-dependent anticoagulant

EDTA-dependent pseudothrombocytopenia (PTCP) is characterised by a low platelet count caused by autoantibodies in the serum reacting with EDTA-anticoagulated blood. EDTA-dependent PTCP is caused by a factor that retains EDTA anticoagulation activity in the serum. We report here that a neonate from a mother with PTCP presented with transient low platelet counts when EDTA was used as an anticoagulant. To confirm the transmission of a maternal serum factor to the neonate, we examined to add the maternal serum into the normal blood. Platelet count decreased significantly after adding maternal serum. Clumped platelets were also observed in the smears of mixed samples.     

Concomitant spuriously elevated white blood cell count,a previously underestimated phenomenon in EDTA-dependent pseudothrombocytopenia

The proportion and potential risk of concomitant spuriously elevated white blood cell count (SEWC) are underestimated in ethylenediaminetetraacetic acid (EDTA)-dependent pseudothrombocytopenia (PTCP). The proportion, kinetics and prevention of SEWC remain poorly understood. A total of 25 patients with EDTA-dependent PTCP were enrolled in this study. With the hematology analyzer Coulter LH 750, we determined the time courses of WBC count, WBC differential and platelet count in EDTA- and sodium citrate-anticoagulated blood, respectively. Blood smears were prepared to inspect the presence of platelet clumps using light microscopy. The effect of automatic instrumental correction on the extent of SEWC was evaluated. The proportion of SEWC was 92% in EDTA-dependent PTCP and 73.9% of SEWCs were within the normal range. The development of SEWC was time-dependent, and neutrophils and lymphocytes were the main subpopulations involved in SEWC. A strong and significant correlation (r?=?0.9937, p?<?0.001) was found between the increased WBC count and the decreased platelet count. Both corrected and uncorrected WBC counts at 15 minutes or later after blood collection in EDTA were significantly higher than their basal counts, respectively, p?<?0.05. Interestingly, in citrated blood, WBC counts after blood collection were not significantly different from its basal counts, p?>?0.05. A high proportion of concomitant SEWCs, which are mainly within normal range, are present in patients with EDTA-dependent PTCP. Proper interpretation of SEWC is crucial to avoid clinic errors. SEWC develops in a time-dependent pattern, although the Coulter LH 750 only partly mitigates the extent of SEWC, sodium citrate is able to effectively prevent SEWC.     

Flow cytometric analysis of platelet activation under calcium ion‐chelating conditions

Platelet activation and aggregation results in factitious counting and sizing in routine haematology testing. In this study, the possibility of platelet activation in anticoagulated solutions was examined. Whole blood was examined using an automated counter and a flow cytometer before and after strong vortex agitation. Blood treated with ethylenediaminetetraacetic acid (EDTA) exhibited platelet activation both pre‐ and postagitation but activated platelets did not cause platelet aggregation. With sodium citrate, platelets were only minimally activated both pre‐ and postagitation. Heparin‐treated blood exhibited minimal platelet activation preagitation, but agitation resulted in strong platelet activation and aggregation. Platelet size was increased by agitation in blood with EDTA and with sodium citrate, in association with significant increases in mean platelet volume (MPV) and platelet distribution width (PDW), but MPV and PDW were significantly higher in EDTA solution than in sodium citrate solution. Change in platelet size was observed even in the presence of EDTA, indicating that careful sampling and processing are needed in the collection of specimens. Specimens obtained from patients with EDTA‐dependent pseudothrombocytopenia exhibited the same level of activation as controls, although platelets exhibited aggregation in such specimens. In conclusion, platelet activation involving platelet size change can occur in the absence of calcium ions in blood treated with EDTA.     

A case of late-onset SLE complicated with EDTA-dependent pseudothrombocytopenia]

A 57-year-old man was admitted to our clinic with complaints of proximal myalgia in extremities. He was diagnosed as late-onset SLE based on the findings of pleuritis, pericarditis, arthritis and antibodies to DNA and cardiolipin. Aggregation of the platelets and the decreased counts of platelets were observed when EDTA was used as anticoagulant for the blood tests. However, the platelet aggregation was not noted with normal counts of platelets when Heparin-Theophylline was used as anticoagulant. From this observation, EDTA-dependent pseudothrombocytopenia was diagnosed and IgM class of EDTA-dependent anti-platelet antibody was detected by means of flow cytometry. Administration of prednisolone at 40mg/day reduced the symptoms and EDTA-dependent pseudothrombocytopenia, and EDTA-dependent anti-platelet antibody disappeared. His clinical course suggested that EDTA-dependent pseudothrombocytopenia was closely associated with the disease activity of SLE.     

乙二胺四乙酸盐依赖性血小板假性减少症与获得性自身免疫的关系

目的：探讨乙二胺四乙酸盐（EDTA）依赖性血小板假性减少症的发生与获得性自身免疫病的关系。方法：采用血细胞分析仪测定恶性肿瘤患者化疗前后血小板数量,与手工计数法测得的血小板数量相比较;确定恶性肿瘤患者化疗前后EDTA依赖性血小板假性减少症的发生率。结果：经化学治疗后的恶性肿瘤患者EDTA依赖性血小板假性减少症的发生率较化疗前明显增高。结论：EDTA依赖性血小板假性减少症与获得性自身免疫病相关联。     

Role of GPIIb-IIIa in platelet-monocyte and platelet-neutrophil conjugate formation in whole blood

Platelets in stirred whole blood can be induced to form aggregates and also to form heterotypic platelet-monocyte (P/M) and platelet-neutrophil (P/N) conjugates. Here we have investigated the effects of three GPIIb-IIIa antagonists (GR144053F, MK-852 and Reopro, a CD62P-blocking antibody, GA6, and EDTA on the conjugate formation that occurs on stirring whole blood and in response to adding ADP and PAF. We have confirmed the identities of the conjugates by light microscopy after cell sorting. Platelet aggregation was measured by platelet counting. Monocytes, neutrophils, P/M and P/N were detected and quantitated using immunofluorescence and flow cytometry. Stirring whole blood resulted in both platelet aggregation and formation of P/M but not P/N. Adding ADP or PAF to whole blood caused rapid platelet aggregation and generation of both P/M and P/N. All of the GPIIb-IIIa antagonists studied had similar effects: inhibition of stirring-induced platelet aggregation and P/M formation, and inhibition of ADP-induced platelet aggregation and P/N formation. In contrast, they accelerated ADP induced-P/M conjugate formation and PAF-induced formation of both P/M and P/N. Both EDTA and GA6 completely inhibited P/M and P/N, which is commensurate with CD62P being involved in platelet-leucocyte conjugate formation. The results of these investigations suggest that GPIIb-IIIa has a dual role in determining the interaction between platelets and leukocytes.     

Role of GPIIb-IIIa in platelet-monocyte and platelet-neutrophil conjugate formation in whole blood

Platelets in stirred whole blood can be induced to form aggregates and also to form heterotypic platelet-monocyte (P/M) and platelet-neutrophil (P/N) conjugates. Here we have investigated the effects of three GPIIb-IIIa antagonists (GR144053F, MK-852 and ReoproTM, a CD62P-blocking antibody, GA6, and EDTA on the conjugate formation that occurs on stirring whole blood and in response to adding ADP and PAF. We have confirmed the identities of the conjugates by light microscopy after cell sorting. Platelet aggregation was measured by platelet counting. Monocytes, neutrophils, P/M and P/N were detected and quantitated using immunofluorescence and flow cytometry. Stirring whole blood resulted in both platelet aggregation and formation of P/M but not P/N. Adding ADP or PAF to whole blood caused rapid platelet aggregation and generation of both P/M and P/N. All of the GPIIb-IIIa antagonists studied had similar effects: inhibition of stirring-induced platelet aggregation and P/M formation, and inhibition of ADP-induced platelet aggregation and P/N formation. In contrast, they accelerated ADP induced-P/M conjugate formation and PAF-induced formation of both P/M and P/N. Both EDTA and GA6 completely inhibited P/M and P/N, which is commensurate with CD62P being involved in platelet-leucocyte conjugate formation. The results of these investigations suggest that GPIIb-IIIa has a dual role in determining the interaction between platelets and leukocytes.