title: Heparin-induced thrombocytopenia.
abstract: Heparin-induced thrombocytopenia (HIT) is caused by platelet-activating immunoglobulin (Ig) G antibodies that recognize multimolecular complexes of platelet factor 4 (PF4) bound to heparin or other polyanions. Most laboratory assays for HIT have a high sensitivity for anti-PF4/heparin antibodies and a negative test generally excludes HIT (high negative predictive value), especially in a setting of a low pretest probability. The magnitude of a positive test result correlates with greater likelihood of HIT. Therefore, a combined diagnostic approach that considers the clinical picture and the magnitude of a positive test result is recommended for accurate diagnosis of HIT.
authors.affiliation: Institute for Immunology and Transfusion Medicine, Ernst-Moritz-Arndt-University, Greifswald, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Greinacher
authors.forename: Birgitt
authors.initials: B
authors.lastname: Fürll
authors.forename: Sixten
authors.initials: S
authors.lastname: Selleng
mesh_terms: D000925:Anticoagulants / Q000009:adverse effects* / Q000276:immunology / Q000378:metabolism; D001777:Blood Coagulation; D004797:Enzyme-Linked Immunosorbent Assay; D006493:Heparin / Q000009:adverse effects* / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D015539:Platelet Activation / Q000276:immunology; D010978:Platelet Factor 4 / Q000276:immunology / Q000378:metabolism; D013921:Thrombocytopenia / Q000139:chemically induced / Q000175:diagnosis* / Q000276:immunology
chemical_list: D000925:Anticoagulants; D007074:Immunoglobulin G; D010978:Platelet Factor 4; D006493:Heparin