title: [Heparin-induced thrombocytopenia].
abstract: Hemorrhage is the most common and best-recognized complication of heparin treatment. However, a potentially more dangerous complication is the development of heparin-induced thrombocytopenia (HIT). All patients exposed to heparin, irrespective of the dose and route of administration, are at risk of developing HIT. It is due to the formation of antibodies against the heparin-platelet factor 4 complex, which cause secondary activation of platelets, coagulation and, finally, increased thrombin production. The main symptom is the sudden onset of thrombocytopenia involving a drop in the platelet count to less than 50% of the basal level, with or without the appearance of thrombotic complications some 5 to 14 days after the start of heparin therapy. Heparin-induced thrombocytopenia can be detected early in patients receiving heparin by monitoring the platelet count. Demonstration of heparin-dependent platelet activation using an antigen or functional assay confirms the clinical diagnosis. Once the diagnosis of HIT has been confirmed serologically or there is a high level of suspicion of HIT, heparin must be suspended and treatment with an alternative anticoagulant should be considered. This review contains a discussion of the diagnosis and treatment of this syndrome.
authors.affiliation: Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Cruz-González
authors.forename: María
authors.initials: M
authors.lastname: Sánchez-Ledesma
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Sánchez
authors.forename: Ik-Kyung
authors.initials: IK
authors.lastname: Jang
mesh_terms: D000925:Anticoagulants / Q000009:adverse effects* / Q000276:immunology / Q000627:therapeutic use; D001120:Arginine / Q000031:analogs & derivatives; D002809:Chondroitin Sulfates / Q000627:therapeutic use; D003871:Dermatan Sulfate / Q000627:therapeutic use; D005343:Fibrinolytic Agents / Q000009:adverse effects* / Q000276:immunology / Q000627:therapeutic use; D000077425:Fondaparinux; D006493:Heparin / Q000009:adverse effects* / Q000276:immunology; D006497:Heparan Sulfate / Q000627:therapeutic use; D006629:Hirudins; D006801:Humans; D010446:Peptide Fragments / Q000627:therapeutic use; D010875:Pipecolic Acids / Q000627:therapeutic use; D011134:Polysaccharides / Q000627:therapeutic use; D011994:Recombinant Proteins / Q000627:therapeutic use; D013449:Sulfonamides; D013921:Thrombocytopenia / Q000139:chemically induced* / Q000175:diagnosis / Q000628:therapy
chemical_list: D000925:Anticoagulants; D001120:Arginine; D002809:Chondroitin Sulfates; D003871:Dermatan Sulfate; D005343:Fibrinolytic Agents; D000077425:Fondaparinux; D006493:Heparin; D006497:Heparan Sulfate; D006629:Hirudins; D010446:Peptide Fragments; D010875:Pipecolic Acids; D011134:Polysaccharides; D011994:Recombinant Proteins; D013449:Sulfonamides; C035838:danaparoid; C031942:argatroban; C074619:bivalirudin