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Updated: May 27, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
A case of factor V inhibitor with complete correction of the PT and aPTT upon mixing
Jay Lipshitz1, Thandavababu Chelliah, Louis Aledort
1Division of Hematology/Oncology, Maimonides Medical Center, Brooklyn, NY, USA. jlipshitz@maimonidesmed.org
Abstract:
We read with interest Gartrell's recent report of a woman who developed a factor V inhibitor. Gartrell noted in his report that the inhibitor appeared to exhibit time dependence, as the mixing study showed slightly more prolongation of both the PT and the aPTT after 1 hr than immediately following mixing. We believe Gartrell's article may shed light on a recent intriguing case of a patient with factor V inhibitor at our institution.
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