Ahmad Sarfraz
Florida Hospital Medical Center, Cancer Institute, Orlando, FL 32804, USA.
Front Biosci. 2007 May 1;12:3312-20. doi: 10.2741/2314.
Heparin-induced thrombocytopenia (HIT) is a complication of heparin therapy in cardiovascular/hematologic indications. Heparin is a mixture of sulfated mucopolysaccharide with heterogeneity and is capable of forming multiple complexes with platelet factor 4 (PF4), released from activated platelets. HPF4 antibodies may cause platelet/endothelial cell activation to promote HIT pathogenesis. HIT is a clinico-pathologic syndrome and its diagnosis primarily remains a clinical one; however, the serologic confirmation of the presence of HPF4 antibodies is also necessary part of the evaluation. Assays are based on the immunodetection of HPF4 antibodies and/or their functional ability to activate cells. Currently, there are several assays in use and a few newer/rapid immunoassays are becoming available. Recent studies have confirmed that HPF4 antibody generation (seroconversion) is common after cardiac surgery and suggest that patients receiving bovine heparin are more likely to generate functional (pathogenic) HPF4 antibodies of the IgG subclass. Thus, the use of bovine heparin in cardiovascular surgery should be avoided. A brief account of the currently available options for the management of HIT patients with non-heparin anticoagulants is provided.
肝素诱导的血小板减少症（HIT）是心血管/血液学适应症中肝素治疗的一种并发症。肝素是一种具有异质性的硫酸化粘多糖混合物，能够与活化血小板释放的血小板因子4（PF4）形成多种复合物。HPF4抗体可能导致血小板/内皮细胞活化，从而促进HIT的发病机制。HIT是一种临床病理综合征，其诊断主要仍依赖临床诊断；然而，血清学确认HPF4抗体的存在也是评估的必要部分。检测基于HPF4抗体的免疫检测和/或其激活细胞的功能能力。目前，有几种检测方法正在使用，一些更新的/快速免疫检测方法也即将问世。最近的研究证实，心脏手术后HPF4抗体产生（血清转化）很常见，并表明接受牛肝素治疗的患者更有可能产生IgG亚类的功能性（致病性）HPF4抗体。因此，应避免在心血管手术中使用牛肝素。本文简要介绍了目前使用非肝素抗凝剂治疗HIT患者的可用选择。
