[Clinical study of heparin-induced thrombocytopenia]

To observe the incidence of heparin-induced thrombocytopenia (HIT) in patients received unfractionated heparin (UFH) treatment, and explore the feasibility of monitoring HIT by platelet counts, as well as the significance of HIT-antibody test in HIT diagnosis.

145 patients received UFH treatment in Vascular Surgery Department were studied. Before and after the UFH treatment, platelet counts, HIT-antibody ELISA test and heparin-induced platelet aggregation (HIPA) were tested.

Among the 145 patients, thrombocytopenia occurred in 40 (27.6%) cases, HIT-antibody ELISA test positive in 59 (40.7%) cases, HIPA test positive in 26 (17.9%) cases. The HIT was diagnosed in 24 (16.5%) cases, and heparin-induced thrombocytopenia and thrombosis (HITTS) occurred in 5 (3.4% in all cases, and 20.8% in HIT patients). In HIT patients, 15 patients (62.5%) were thrombocytopenia, HIT-antibody positive and HIPA test positive. Platelet counts in all of the 24 patients recovered to normal or level before UFH treatment in 3-6 days after heparin withdrawal therapy.

HIT can be early diagnosed by monitoring platelet counts, HIT-antibody ELISA test and HIPA test. Withdrawal of heparin therapy in time and use of alternative anticoagulant, HITTS rate might be expected to decline further.