Department of Haematology, Immune Response and Vascular Disease Unit, Nova University Lisbon, Lisbon, Portugal.
Department of Haematology, Dumfries Royal Infirmary, Cargenbridge, Dumfries, UK.
Rheumatology (Oxford). 2023 Jun 1;62(6):2070-2075. doi: 10.1093/rheumatology/keac650.
Thrombosis associated with thrombocytopaenia is an apparent paradox that is present across a wide spectrum of disorders. While thrombocytopaenia has been a controversial clinical classification criterion for APS, as initial reports failed to demonstrate a relation between low platelet count with other clinical or laboratory manifestations of the syndrome, recent data highlight the association between mild-moderate thrombocytopaenia and the risk of thrombosis. Although aPL antibodies may induce platelet activation in vitro, additional stimuli may contribute to their activation in vivo, among which are reactive oxygen and nitrogen species and lipid peroxidation products, which are elevated in patients with APS; an excess of the same stimuli may induce megakaryocyte and platelet apoptosis that leads to decreased platelet production and increased destruction, resulting ultimately in thrombocytopaenia. Herein we provide a novel plausible framework involving free radicals that could add to the understanding of the thrombocytopaenia-thrombosis paradox in APS.
血栓形成与血小板减少症是一种广泛存在于多种疾病中的明显悖论。虽然血小板减少症一直是 APS 的一个有争议的临床分类标准，但最初的报告未能显示低血小板计数与该综合征的其他临床或实验室表现之间存在关系，最近的数据强调了轻度至中度血小板减少症与血栓形成风险之间的关联。尽管 aPL 抗体可能在体外诱导血小板活化，但体内可能存在其他刺激因素导致其活化，其中包括活性氧和氮物种以及脂质过氧化产物，这些物质在 APS 患者中升高；过量的相同刺激因素可能诱导巨核细胞和血小板凋亡，导致血小板生成减少和破坏增加，最终导致血小板减少症。在此，我们提供了一个新的合理框架，涉及自由基，这可能有助于理解 APS 中血小板减少症-血栓形成悖论。
