000			02385nam a2200253 4500
001			ESSALUD
007			ta
008			t pe ||||| |||| 00| 0 spa d
040			_aBMG
041			_aspa
100			_aWarkentin, Theodore E. _eAutor _953833
245			_aPlatelet-activating anti–platelet factor 4 disorders
300			_apáginas: 478-491
520			_aPlatelet-activating antibodies against platelet factor 4 (PF4) cause highly prothrombotic disorders with reduced platelet counts. In heparin-induced thrombocytopenia (HIT), these antibodies bind PF4–heparin complexes, causing heparin-dependent platelet activation. Less common autoimmune and spontaneous HIT variants that are triggered by heparin and nonpharmacologic polyanions, respectively, have atypical clinical features and antibodies with additional heparin-independent platelet-activating properties. Vaccine-induced immune thrombocytopenia and thrombosis (VITT) antibodies directly target PF4. Initially, VITT was linked to adenoviral vector–based coronavirus disease 2019 vaccines, but in rare cases, an immune thrombocytopenia and thrombosis disorder that is clinically nearly identical to VITT can be caused by infection resulting from natural exposure to viruses, especially adenovirus. In persons with the IGLV3-21*02/*03 gene, anti–adenovirus protein VII antibody specificity shifts to PF4 by way of a specific somatic hypermutation (K31E) that creates VITT antibodies. In VITT-like monoclonal gammopathy of thrombotic significance, monoclonal anti-PF4 antibodies cause chronic prothrombotic conditions. Accurate diagnosis relies on distinct assays for HIT and VITT antibodies. Beyond anticoagulation, inhibition of FcγIIa receptor–mediated platelet activation may be needed for anti-PF4 disorders with heparin-independent reactivity (e.g., high-dose immune globulin in acute disease manifestations and Bruton’s tyrosine kinase inhibitors in chronic manifestations).
650			_aANTICOAGULACION _953834
650			_aTROMBOEMBOLISMO _932218
650			_aANTICOAGULACION _953834
650			_aVACUNAS _98158
650			_aCORONAVIRUS _939659
650			_aINFECCIONES VIRALES _953766
700			_aGreinacher, Andreas _953835
773	0		_022717 _922638 _dMassachusetts NEJM Group _oNEJM005 _tThe New England Journal of Medicine _wESSALUD _x0028-4793
942			_cARTICULOS _e2026-07-31 _zSQB
999			_c22754 _d22754