Angela Napolitano, Luca Spiezia, Marta Biolo, Claudia Maria Radu, Serena Toffanin, Elena Campello, Paolo Simioni
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引用次数: 0
Abstract
Anti-platelet factor 4 (PF4) antibody-mediated disorders are a heterogeneous group of diseases characterized by the presence of highly pathogenic immunoglobulins G directed against PF4 and/or PF4/heparin complexes. These antibodies are able to activate platelets, neutrophils, and monocytes, thus resulting in thrombocytopenia and a hypercoagulable state. Five different forms of anti-PF4 antibody-mediated disorders have been identified: (1) classic heparin-induced thrombocytopenia (HIT) mediated by heparin and certain polyanionic drugs; (2) autoimmune HIT characterized by the presence of anti-PFA/polyanion antibodies that can strongly activate platelets even in the absence of heparin; (3) spontaneous HIT characterized by thrombocytopenia and thrombosis without proximate exposure to heparin, with two subtypes: (a) post-total knee arthroplasty and cardiac surgery using cardiopulmonary bypass or extracorporeal membrane oxygenation and (b) postinfections; (4) vaccine-induced immune thrombotic thrombocytopenia (VITT) characterized by thrombocytopenia, arterial and venous thrombosis, or secondary hemorrhage after receiving adenoviral vector vaccines for coronavirus disease 2019; (5) VITT-like disorders triggered by adenoviral infections. Although extremely rare and largely unknown, there has been growing interest in the VITT syndrome in recent years due to its clinical relevance. Timely detection of these antibodies is crucial for the diagnosis and treatment of anti-PF4 antibody-mediated disorders, via anti-PF4 antibody immunoassays using several antibody capture systems (e.g., enzyme-linked immunosorbent assay-based, particle gel, turbidimetry) and functional assays (e.g., serotonin release assay or heparin-induced platelet activation). We aimed to present the latest on laboratory findings, clinical characteristics, and therapeutic approaches for anti-PF4 antibody-mediated disorders.
期刊介绍:
Seminars in Thrombosis and Hemostasis is a topic driven review journal that focuses on all issues relating to hemostatic and thrombotic disorders. As one of the premiere review journals in the field, Seminars in Thrombosis and Hemostasis serves as a comprehensive forum for important advances in clinical and laboratory diagnosis and therapeutic interventions. The journal also publishes peer reviewed original research papers.
Seminars offers an informed perspective on today''s pivotal issues, including hemophilia A & B, thrombophilia, gene therapy, venous and arterial thrombosis, von Willebrand disease, vascular disorders and thromboembolic diseases. Attention is also given to the latest developments in pharmaceutical drugs along with treatment and current management techniques. The journal also frequently publishes sponsored supplements to further highlight emerging trends in the field.