ISSN 2997-1036
International Journal of Hematology | Vol. 2, No. 11, November 2011 | pp. 81–88
DOI: 10.46882/2011/IJH/000023
Review Article
Title: Pathophysiological mechanisms and clinical therapeutic targets in heparin-induced thrombocytopenia
Names of Authors: M. A. Bello¹, O. R. Eze²
Authors’ Affiliations: ¹Department of Haematology, Aminu Kano Teaching Hospital, Kano, Nigeria; ²Department of Pathology, University of Benin, Benin City, Nigeria
Abstract: Heparin-induced thrombocytopenia is a paradoxically prothrombotic immune-mediated drug reaction driven by pathogenic IgG antibodies targeting platelet factor 4-heparin complexes. This review synthesizes current insights into cellular interaction mechanisms, emphasizing antibody-mediated Fc-gamma-RIIa receptor cross-linking on platelets, which triggers rapid microparticle release, thrombin generation, and subsequent endothelial injury. Clinical diagnosis relies on scoring systems like the 4Ts algorithm, supported by functional serotonin release assays or enzyme-linked immunosorbent antibody screening. Management mandates the immediate cessation of all heparin formulations and the initiation of rapid-acting non-heparin anticoagulants. Direct thrombin inhibitors like argatroban and factor Xa inhibitors like fondaparinux achieve systemic anticoagulation without cross-reacting with heparin-induced antibodies. Initiating warfarin is strictly contraindicated during the acute thrombocytopenic phase due to the risk of microvascular thrombosis and skin necrosis from protein C depletion. This review presents structured management pathways to optimize patient selection, minimize systemic bleeding risks, and prevent thrombotic limb loss in intensive care populations.
Keywords: Heparin-induced thrombocytopenia, platelet factor 4, argatroban, thrombosis, anticoagulation
Manuscript Timeline: Received: August 11, 2011; Revised: September 22, 2011; Accepted: October 15, 2011; Published: November 18, 2011