Heparin-Induced Thrombocytopenia : A Contemporary Clinical Approach to Diagnosis and Management

Thrombocytopenia following heparin administration can be associated with an immune reaction, now referred to as heparin-induced thrombocytopenia. HIT is essentially a prothrombotic disorder mediated by an IgG antiplatelet factor 4/heparin antibody, which induces platelet, endothelial cell, monocyte, and other cellular activation, leading to thrombin generation and thrombotic complications. Indeed, HIT can also be regarded as a serious adverse drug effect. Importantly, HIT can be a life-threatening and limb-threatening condition frequently associated with characteristically severe and extensive thromboembolism rather than with bleeding. This article provides an overview of HIT, with an emphasis on the clinical diagnosis and management.