Abstract
Heparin-induced thrombocytopenia (HIT) is a drug-mediated, prothrombotic disorder caused by immunization against platelet factor 4 (PF4)/heparin complexes. A subset of anti-PF4 /heparin antibodies is capable of intravascular platelet activation by cross-linking Fcγ receptor IIA leading to platelet count decrease and/or thrombosis. HIT can be potentially associated with devastating complications such as life-threatening thrombosis. Therefore, if HIT is strongly suspected, all sources of heparin must be stopped and an alternative non-heparin anticoagulant should be started to prevent new thromboembolic complications. However, the diagnosis of HIT based on clinical information is often difficult. This review highlights the pathophysiology of HIT, emphasizing characteristic clinical features and the role of laboratory assays in the diagnosis of HIT. In addition, a summary of current therapeutic options for patients with HIT will be provided.
