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Updated: Mar 20, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Clinical manifestations in 28 Italian and Iranian patients with severe factor VII deficiency
F Peyvandi1, P M Mannucci1, D Asti1
1Angelo Bianchi Bonomi Hemophilia and Thrombosis Center and the Institute of Internal Medicine, IRCCS Maggiore Hospital and University of Milan, Italy,Hemophilia Center, University of Tehran, Islamic Republic of Iran.
Abstract:
There has been wide variation in the reported haemorrhagic manifestations of factor VII deficiency. We examined type and frequency of clinical manifestations in 28 Iranian and Italian patients with severe deficiency (factor VII coagulant activity 2% or less). The most frequent symptoms were epistaxis and menorrhagia, whereas soft tissue bleeding such as haemarthrosis and muscle haematoma was less frequent. Only 5 of 9 patient who underwent surgery without factor VII replacement therapy had postoperative bleeding severe enough to require blood transfusion. No thrombotic manifestation occurred. A factor VII functional assay based on the use of human thromboplastin was a better predictor of the bleeding tendency of these patients than a rabbit thromboplastin-based functional assay or immunoassay. On the whole, this study shows that in severe factor VII deficiency bleeding in mucosal tracts is not uncommon. Surgery can sometimes be performed without replacement therapy and without haemorrhagic complications.
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