Schell D A, Ganti A K, Levitt R, Potti A
Department of Internal Medicine, University of North Dakota School of Medicine and Health Sciences, 1919 N Elm Street, Fargo, ND 58102, USA.
Ann Hematol. 2002 Feb;81(2):76-9. doi: 10.1007/s00277-001-0414-7. Epub 2002 Jan 18.
Abciximab (c7E3 Fab) inhibits platelet aggregation and is used to prevent complications of percutaneous coronary intervention. Thrombocytopenia is an often-cited complication of abciximab. Pseudothrombocytopenia is due to ethylenediaminetetraacetate (EDTA)-activated platelet agglutination, resulting in a spuriously low platelet count. We have looked at both "true" and pseudothrombocytopenia after infusion of abciximab. Sixty-six patients receiving their first exposure to abciximab after an unstable coronary event/revascularization were eligible. All the patients received a bolus of c7E3 Fab followed by a continuous infusion. Platelets were monitored in all patients at 2, 4, 12, 24, and 48 h, and more frequently if required. The incidence of thrombocytopenia and acute severe thrombocytopenia (platelet count < or =20,000/microl) was evaluated. A peripheral blood smear was performed on all patients showing thrombocytopenia to evaluate for pseudothrombocytopenia. Seventeen (25.6%) developed thrombocytopenia and nine (13.6%) developed acute severe thrombocytopenia. However, 18 of these patients had pseudothrombocytopenia. The onset of true thrombocytopenia was at 4 h after the infusion, while pseudothrombocytopenia occurred at anytime during the first 24 h. Only two (3.03%) patients required platelet transfusions. No life-threatening hemorrhagic complications were recognized. Five of six subjects with true thrombocytopenia had positive laboratory findings of disseminated intravascular coagulation; however, none had an adverse outcome. Acute severe thrombocytopenia was noted to be a relatively benign adverse effect of abciximab. There is an increasing incidence of pseudothrombocytopenia in this subgroup of patients. It would be worthwhile examining a peripheral blood smear or collecting blood for platelet counts in a heparin-coated tube in order to exclude this phenomenon and thereby prevent inappropriate discontinuation of this drug.
阿昔单抗（c7E3 Fab）可抑制血小板聚集，用于预防经皮冠状动脉介入治疗的并发症。血小板减少症是阿昔单抗常被提及的并发症。假性血小板减少症是由于乙二胺四乙酸（EDTA）激活血小板凝集，导致血小板计数假性降低。我们观察了阿昔单抗输注后的“真性”和假性血小板减少症。66例在不稳定型冠状动脉事件/血运重建后首次接受阿昔单抗治疗的患者符合条件。所有患者均先静脉推注c7E3 Fab，随后持续输注。在所有患者输注后2、4、12、24和48小时监测血小板，必要时更频繁监测。评估血小板减少症和急性严重血小板减少症（血小板计数≤20,000/微升）的发生率。对所有出现血小板减少症的患者进行外周血涂片检查，以评估是否存在假性血小板减少症。17例（25.6%）出现血小板减少症，9例（13.6%）出现急性严重血小板减少症。然而，这些患者中有18例存在假性血小板减少症。真性血小板减少症在输注后4小时开始出现，而假性血小板减少症在最初24小时内的任何时间都可能发生。只有2例（3.03%）患者需要输注血小板。未发现危及生命的出血并发症。6例真性血小板减少症患者中有5例实验室检查发现弥散性血管内凝血阳性；然而，无一例出现不良后果。急性严重血小板减少症被认为是阿昔单抗相对良性的不良反应。在该亚组患者中，假性血小板减少症的发生率呈上升趋势。检查外周血涂片或用肝素包被的试管采集血液进行血小板计数以排除这种现象，从而避免不适当停用该药物是值得的。
