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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
Prolonged Partial Thromboplastin Time Without Bleeding History; Fletcher Factor Deficiency
Abstract:
A 67-year-old patient was admitted to the hospital to perform an esophagogastrectomy because a lesion at the lower esophagus was strongly suspicious for cancer. Her medical history and her family history were negative for bleeding tendency or thrombosis. Her activated partial thromboplastin time (aPTT) was prolonged (44 s) whereas her prothrombin time (PT) was normal (11 s) presurgery. Mixing of her plasma with normal plasma corrected her prolonged aPTT (27.9 s). Prolonged incubation shortened the patient's aPTT (36.3 s). Fletcher factor activity was found to be 50%. The patient underwent an esophagogastrectomy without bleeding complications under spinal anesthesia. Fletcher factor deficiency, a rare disorder, should be considered in patients who have no history of bleeding tendency with a prolonged aPTT. Surgical interventions are safe in these patients.
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