Related Experiment Video
Updated: Jun 16, 2025

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
PF4-associated immune thrombocytopenia and thrombosis (PITT)-More than heparin and vaccines
1School of Medicine and Population Health, University of Sheffield, Sheffield, UK.
Abstract:
A young woman presented with portal vein thrombosis and thrombocytopenia and developed further extensive thrombosis following treatment with heparin. Despite no previous heparin exposure, she was found to be strongly positive for anti-platelet factor 4 (PF4) antibodies. She had acute cytomegalovirus (CMV) infection and a monoclonal gammopathy. Commentary on: Nicolson et al. Anti-PF4 mediated thrombocytopenia and thrombosis associated with acute cytomegalovirus infection displays both HIT-like and VITT-like characteristics. Br J Haematol 2025; 206:1737-1742.
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