Factor X Activity
|Profile or Test Panel
|A one-stage extrinsic system clotting assay is used to measure circulating factor X levels. Clotting times of dilutions of patient plasma are compared to dilutions of a plasma pool from normal donors, when added to deficient plasma. Levels are reduced in hereditary or acquired factor X deficiency, factor X inhibitor, vitamin K deficiency, warfarin therapy, liver disease, disseminated intravascular coagulation (DIC), or amyloidosis. With special arrangement, intrinsic system and Russell’s viper venom (RVV) activations can be added for comparison.
|Additional Test Information
|Normal ranges are included on testing report and can be made available upon request.
|Whole Blood: 3.2% sodium citrated (blue top) OR
|Two 5 ml 3.2% sodium citrated (blue top) tubes as whole blood OR
frozen plasma in 4 X 1mL aliquots in plastic tubes
|Minimum Volume or Pediatric Volume
|Frozen Plasma: at least 0.5ml in 2 plastic tubes.
|Whole blood is preferred for testing, but if it is not possible to send whole blood tubes TO ARRIVE HERE within 2 hours of collection, then send frozen plasma. To prepare plasma, centrifuge blue top tubes at 1500g for 15 minutes and remove the plasma and centrifuge a second time at 1500g for an additional 15 minutes. Aliquot approximately 1 ml of plasma into 4 plastic tubes, and freeze.
|Whole Blood: Send at ambient temperature (18-25°C) and must be received within the lab in less than or equal to 2 hours after collection.
Frozen Plasma: Send on dry iceSend samples to:
Attn: Hemostasis Laboratory
921 Terry Ave
Seattle, WA 98104For additional information, please see Ordering Information
|RFT- Hemostasis Reference Laboratory
|Monday – Friday
|Turn around Time (analytic time)
|3 Business Day
|Fax number required to receive report