Factor 2 activity

Alphabetical Test listing

Factor 2 activity-13366

Factor 2 activity
Factor II activity

Evaluate an isolated prolonged PT or when there is prolongation of both the APTT and PT and to document specific factor II deficiency.

Sodium citrate (Na cit) plasma
1.0 mL
  • Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate
  • Evacuated collection tubes must be filled to completion to ensure a proper blood-to-anticoagulant ratio
  • The sample should be mixed immediately by gentle inversion, at least six times, to ensure adequate mixing of the anticoagulant with the blood
  • A discard tube is not required prior to collection of coagulation samples unless the sample is collected using a winged (butterfly) collection system
    • With a winged blood collection set a discard tube should be drawn first to account for the dead space of the tubing and prevent under-filling of the evacuated tube
  • When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes
    • Any tube containing an alternative anticoagulant should be collected after the blue-top tube
    • Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes
  • If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted
  1. Spin
  2. Transfer plasma to a Screw-cap polypropylene frozen transport vial/tube - 4mL (LabCorp), labelled as Na cit plasma, within two (2) hours of sample collection
  3. Freeze




  • Severe hemolysis
  • Improper labeling
  • Clotted specimen
  • Specimen diluted with I.V. fluids
  • Samples thawed in transit
  • Improper sample type
  • Sample out of stability


LabCorp Burlington (086231): R-LC
2 - 3 days

Factor II activity is determined utilizing a Prothrombin Time (PT)-based one-stage clotting time assay. Factor II- depleted plasma is used as the substrate and the clotting time with the patient plasma is compared to the clotting time of normal pooled plasma.


50 - 154%

Result 3289-6