Introduction to Heparin-Induced Thrombocytopenia (HIT)
Heparin-induced thrombocytopenia (HIT) is a serious immune-mediated adverse reaction occurring in patients treated with heparin, a common anticoagulant medication. HIT is characterized by the formation of antibodies against complexes formed by platelet factor 4 (PF4) and heparin. These antibodies activate platelets, leading to a paradoxical prothrombotic state despite the underlying thrombocytopenia. HIT can result in severe complications such as venous and arterial thrombosis, limb ischemia, and even fatal outcomes if not diagnosed and managed promptly.
