Heparin-induced thrombocytopenia

Heparin-induced thrombocytopenia
A schematic drawing of platelet factor 4, which when bound to heparin leads to an immune response in HIT
SpecialtyHematology Edit this on Wikidata

Heparin-induced thrombocytopenia (HIT) is the development of thrombocytopenia (a low platelet count), due to the administration of various forms of heparin, an anticoagulant. HIT predisposes to thrombosis (the abnormal formation of blood clots inside a blood vessel). When thrombosis is identified the condition is called heparin-induced thrombocytopenia and thrombosis (HITT). HIT is caused by the formation of abnormal antibodies that activate platelets, which release microparticles that activate thrombin, leading to thrombosis. If someone receiving heparin develops new or worsening thrombosis, or if the platelet count falls, HIT can be confirmed with specific blood tests.[1]

The treatment of HIT requires stopping heparin treatment, and both protection from thrombosis and choice of an agent that will not reduce the platelet count any further. Several alternatives are available for this purpose; mainly used are danaparoid, fondaparinux, argatroban, and bivalirudin.[2][3]

While purified heparin was first used in humans in the 1930s, HIT was not reported until the 1960s.[4]

  1. ^ Ahmed I, Majeed A, Powell R (September 2007). "Heparin induced thrombocytopenia: diagnosis and management update". Postgrad Med J. 83 (983): 575–82. doi:10.1136/pgmj.2007.059188. PMC 2600013. PMID 17823223.
  2. ^ Watson, H (2012). "Guidelines on the diagnosis and management of heparin-induced thrombocytopenia: second edition". British Journal of Haematology. 159 (5): 528–40. doi:10.1111/bjh.12059. PMID 23043677. S2CID 5104368.
  3. ^ Bakchoul T, Greinacher A (2012). "Recent advances in the diagnosis and treatment of heparin-induced thrombocytopenia". Ther Adv Hematol. 3 (4): 237–51. doi:10.1177/2040620712443537. PMC 3627332. PMID 23606934.
  4. ^ Kelton JG, Warkentin TE (October 2008). "Heparin-induced thrombocytopenia: a historical perspective". Blood. 112 (7): 2607–16. doi:10.1182/blood-2008-02-078014. PMID 18809774.