Vaccine-Induced Thrombotic Thrombocytopenia (VITT)

Laboratory testing for investigation of VITT requires confirmation that the antibody will react with PF4 and produce positive results in the anti‐PF4/heparin immunoassays. Some automated rapid immunoassays for HIT antibodies, such as the chemiluminescence immunoassay (CLIA) may produce negative results. The diagnosis of VITT requires confirmation in a functional assay such as the Serotonin Release Assay (SRA) with heparin (standard SRA) and with PF4 added instead of heparin. These tests were developed and are currently available in the McMaster Platelet Immunology Laboratory..

Test Methods:

Serotonin Release Assay (SRA) and modified SRA and PF4/heparin EIA

Information and Form: