Heparin-Induced Thrombocytopenia (HIT) is a common prothrombotic complication of UFH and LMWH therapies.
HIT is caused by antibodies directed against heparin-platelet factor 4 complexes (H-PF4). These are capable of activating platelets, but also endothelial cells and monocytes, inducing tissue factor expression, thrombin generation and fibrin clot formation. The platelet and blood coagulation activation events contribute to the thromboses observed in many patients with HIT.
The diagnosis of HIT is based on clinical criteria (scoring system: 4T's) and is confirmed by in vitro demonstration of H-PF4 antibodies using functional and immunoassays (EIAs). This combination (pre-test scoring + laboratory testing) provides the highest predictivity for HIT.
Functional assays rely on the ability of the H-PF4 antibody to activate platelets in the presence of heparin, while the immunoassays confirm the presence of the antibody without consideration for its ability to cause platelet activation.
In addition to the existing Asserachrom® HPIA, Stago has developed Asserachrom® HPIA – IgG, a highly sensitive and specific ELISA for detecting H-PF4 antibodies of the IgG class.
In clinical studies performed on >400 samples, Asserachrom® HPIA-IgG demonstrated 100% sensitivity, high specificity and concordance with the serotonin release assay of ~92%. This new kit has maintained the high sensitivity of the polyspecific Asserachrom® HPIA (100%), with a superior specificity (92.3%).
Asserachrom® HPIA – IgG is provided in a strip format adapted for the economic analysis of a small test series. Together with excellent reproducibility this allows for an accurate detection of HIT antibodies. The kit can be adapted to automated ELISA instruments.
Setting new standards in the laboratory diagnosis of HIT, Asserachrom® HPIA – IgG results can be used in combination with clinical data for determining the most appropriate anticoagulation therapy in patients with suspected HIT.