Jackson S P, Jane S M, Mitchell C A, Fernando Cortizo W, Hau L, Pfueller S L, Salem H H
Department of Medicine, Monash Medical School, Prahran, Victoria, Australia.
Thromb Haemost. 1989 Nov 24;62(3):846-9.
We report the case of a 50-year-old lady who presented with arterial thrombosis in the setting of thrombocytopenia. Investigations confirmed the diagnosis of idiopathic thrombocytopenic purpura. A spontaneous platelet aggregating factor (SPAF) was isolated from the immunoglobulin fraction of the patient's plasma. The isolated IgG irreversibly aggregated platelet-rich plasma and washed platelets, an effect abolished by pretreating the platelets with aspirin. The activity of the IgG was greatly enhanced by subaggregatory concentrations of thrombin and adrenalin and was localized to the F(ab')2 of the molecule. Plasmapheresis in combination with anti-platelet therapy resulted in an increase in the patient's platelet count, reduced platelet aggregating activity of plasma and significant clinical improvement. We suggest that the presence of this platelet aggregating IgG contributed to the development of thrombosis in our patient and postulate that a similar factor may explain the paradox of thrombosis observed in a select group of thrombocytopenic patients.
我们报告了一例50岁女性患者,该患者在血小板减少的情况下出现动脉血栓形成。检查确诊为特发性血小板减少性紫癜。从患者血浆的免疫球蛋白部分分离出一种自发性血小板聚集因子(SPAF)。分离出的IgG使富含血小板的血浆和洗涤后的血小板发生不可逆聚集,用阿司匹林预处理血小板可消除这种作用。凝血酶和肾上腺素的亚聚集浓度可大大增强IgG的活性,且该活性定位于分子的F(ab')2片段。血浆置换联合抗血小板治疗使患者血小板计数增加,血浆血小板聚集活性降低,并取得了显著的临床改善。我们认为,这种血小板聚集性IgG的存在促成了我们患者血栓形成的发展,并推测类似的因子可能解释了在一组特定血小板减少患者中观察到的血栓形成悖论。