There are two types of HIT with a distinct etiology. Type 1 HIT is a relatively mild thrombocytopenia of early onset that generally resolves with ongoing heparin therapy.
Clinical complications are uncommon.
Type 2 HIT, which is more severe, is the main focus of this report. Five patients receiving heparin therapy developed type 2 HIT, which in some cases resulted in complications that required limb amputation, or eventuated in death. Prompt management of HIT can help prevent complications. In spite of the thrombocytopenia, thrombosis or disseminated intravascular coagulation can occur. Heparin-induced thrombocytopenia is an uncommon but potentially serious, and sometimes lethal, complication of heparin therapy.