24th July 2024

Heparin-induced thrombocytopenia/with thrombosis

This is a rare complication of heparin therapy, more common with UFH than LMWH.

Antibodies are produced against platelet factor 4 (PF4)-heparin complex. This leads to thrombocytopenia and, conversely, thrombosis.

Clinical features of HIT/T

HIT/T should be suspected with new thrombocytopenia, venous or arterial thrombosis or necrosing skin lesions at the site of heparin injection. There are assays to detect the presence of PF4-heparin antibodies and their ability to bind and activate platelets.

Management of HIT/T

Heparin should be discontinued and a non-heparinoid anticoagulant considered such as argatroban, danaparoid or bivalirudin.