Diagnostic strategy in heparin induced thrombocytopenia

Heparin-induced thrombocytopenia occurs due to the formation of antibodies against the complex formed between heparin and platelet factor 4 (H-PF4) leading to platelet/endothelial cell activation followed by thrombocytopenia. Diagnosis of H-PF4 antibodies are mainly based on two different assays; functional and immunologic assays. While the functional assays are based on the platelet activation, the immunogical assays are based on the binding of IgG antibodies to H-PF4 complexes. Even though 14C-Serotonin Release Assay is high in sensitivity, the most commonly used functional assays are Platelet aggregation test and Heparin-ınduced platelet aggregation The immunologic assays include solid-phase detection, fluid-phase detection, enzyme-linked lmmunosorbent assay, particle gel immunoassay; the commonly used is enzyme-linked ımmunosorbent assay occurrence of HIT may vary not only based on the patients’ group but also based on the type of diagnostic technique used. The methodological variations observed in our experience are discussed in this review. In the current review we discuss the diagnostic approach, importance in the diagnosis of Fc?RIIa receptor polymorphism, controversies in diagnosis of HIT and preventive measures.