Currently available enzyme immunoassays for antibodies against
heparin-platelet factor 4 complex allow for sensitive detection of HIT, and the gold standard serotonin-release assay may also be used under some circumstances.
HIT-Type 2 is a severe immune-mediated drug reaction caused by antibodies to the
heparin-platelet factor 4 (PF4) complexes, which can occur in any patient exposed to heparin (Tang et al., 2005).
Heparin-induced thrombocytopenia is a distinctive drug-induced thrombocytopenia associated with heparin therapy, where antibodies are formed to
heparin-platelet factor 4 complexes, leading to platelet aggregation, platelet microparticle formation, endothelial injury, and paradoxical thrombosis.