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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Factor X Chromogenic Activity, Vitamin K Antagonist Therapy

Test Code(s): MISC / RMISC

CPT Code(s): 85260

Testing Site: Testing will be sent to an approved reference laboratory.

Turnaround Time: Routine: 3 - 7 days.

Specimen Requirements

Specimen: Blood

Collection Instructions: Please indicate if patient is receiving anticoagulant (Warfarin/Heparin/Vitamin K antagonist), direct thrombin inhibitor or fibrinolytic agent therapy.

Collection Container: Also Acceptable: Light blue top (3.2% NaCitrate)

Collection Volume: Preferred: 4 mL
Pediatrics: 1.5 mL

Sample Analyzed: Plasma

Volume Required: Preferred: 1 mL
Pediatrics: 0.5 mL

Specimen Processing: Centrifuge specimen to yield platelet poor plasma/serum (platelet count should be less than 10 K/L). Separate plasma/serum and transfer to plastic tube or vial. Freeze plasma/serum at -20C or below.  

Specimen Transport: Transport whole blood specimen at room temperature to UWHC Core Laboratory (B4/220) within 4 hours of collection. See Specimen Processing for instructions if transport criteria are not met.

Outreach Specimen Transport: Transport frozen aliquot on dry ice to UWHC Core Laboratory (B4/220).

Unacceptable Criteria: Hemolyzed specimens, clotted specimens, partially filled tubes and whole blood specimens greater than 4 hours old when received by the laboratory are not acceptable.


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