Heparin-Induced Thrombocytopenia (HIT)

Laboratory testing for investigation of HIT requires confirmation that the antibody will activate platelets in a heparin-dependent manner using a washed-platelet functional assay.  The Serotonin Release Assay (SRA) developed in the McMaster Platelet Immunology Laboratory is the gold standard for the diagnosis of heparin‐induced thrombocytopenia1.  The SRA is a functional test that detects pathologic HIT antibodies with high sensitivity and specificity. The McMaster Platelet Immunology laboratory provides HIT testing using a comprehensive investigation using the Serotonin Release Assay and the anti‐ PF4/heparin EIA.

Test Methods:

Serotonin Release Assay (SRA) and PF4/heparin EIA

Information and Form:


  1. Sheridan D, Carter C, Kelton JG. A diagnostic test for heparin-induced thrombocytopenia. Blood. 1986.