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Updated: Jun 9, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Carriers of factor VII deficiency are not always asymptomatic
Abstract:
Seven children, referred because of bleeding symptoms, proved to be heterozygotes for factor VII deficiency. Abnormal bruising was the commonest symptom (6/7), followed by postoperative bleeding (4/7). One case had recurrent epistaxis. Results on the patients and their families are presented. Prothrombin times were prolonged by 2-3 s and factor VII assays ranged from 25 to 55% (mean 38%). The cases are reported because they bled excessively: yet it is usually stated that carriers for factor VII deficiency are symptom-free. One case of homozygous factor VII deficiency is also described: the parents (who are heterozygotes) were symptom-free.
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