Clinical Presentation and Evaluation of the Utility of the 4T Scoring System in the Diagnosis of Heparin Induced Thrombocytopenia among Patients at Sultan Qaboos University Hospital

The use of heparin have increased in the last years in hospitalized both as prophylaxis and therapeutic. One of the encounter complications of heparin especially with unfractionated heparin though it can be seen with Low molecular weight heparin is thrombocytopenia which could be transient non immune or more badly the immune mediated type heparin induced thrombocytopenia (HIT). Heparin-induced thrombocytopenia is a profoundly dangerous, potentially lethal, immunologically mediated adverse drug reaction to unfractionated heparin or, less commonly to low molecular weight heparin [1]. Despite thrombocytopenia, bleeding is rare; rather, HIT is strongly associated with thromboembolic complications involving both the arterial and venous systems [2]. Recent data show that up to 8% of heparinized patients will develop the antibody associated with HIT and that approximately 1-5% of patients on heparin will progress to develop HIT with thrombocytopenia [3].