May Jori, Westbrook Brian, Cuker Adam
Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Res Pract Thromb Haemost. 2023 Jun 22;7(5):100283. doi: 10.1016/j.rpth.2023.100283. eCollection 2023 Jul.
Heparin-induced thrombocytopenia (HIT) is an immune-mediated adverse drug effect from unfractionated or low-molecular-weight heparin that results in thrombocytopenia and potentially catastrophic thrombosis. HIT occurs due to the development of platelet-activating antibodies against multimolecular complexes of platelet factor 4 and heparin. Given the frequency of thrombocytopenia and heparin use among hospitalized patients, calculation of the 4Ts Score is recommended to identify patients at increased likelihood of HIT and direct further evaluation. In patients with an intermediate or high probability 4Ts Score, an immunoassay and functional assay are recommended to confirm or refute the diagnosis of HIT. Heparin avoidance and initiation of nonheparin anticoagulation are the mainstays of acute HIT management. In this illustrated review, we provide visual summaries of the diagnosis and management of HIT, highlighting connections between pathophysiology and clinical care as well as summarizing efforts in quality improvement in the field. We further emphasize common pitfalls and pearls in diagnosis and management to encourage evidence-based care. We include graphical representation of the unique challenges of HIT with cardiopulmonary bypass and also delineate autoimmune HIT and its subtypes.
肝素诱导的血小板减少症（HIT）是一种由普通肝素或低分子肝素引起的免疫介导的药物不良反应，可导致血小板减少症，并可能引发灾难性血栓形成。HIT的发生是由于针对血小板因子4和肝素的多分子复合物产生了血小板激活抗体。鉴于住院患者中血小板减少症和肝素使用的频率，建议计算4Ts评分以识别HIT可能性增加的患者并指导进一步评估。对于4Ts评分为中度或高度可能性的患者，建议进行免疫测定和功能测定以确诊或排除HIT诊断。避免使用肝素并启动非肝素抗凝是急性HIT管理的主要方法。在本图文综述中，我们提供了HIT诊断和管理的视觉总结，突出了病理生理学与临床护理之间的联系，并总结了该领域质量改进方面的努力。我们进一步强调诊断和管理中的常见陷阱与要点，以鼓励循证护理。我们包括了体外循环下HIT独特挑战的图形表示，还描述了自身免疫性HIT及其亚型。
