Thrombosis Panel

Test Code
11051


CPT Codes
85300, 85303, 85306, 85307

Includes
Protein C Activity
Protein S Activity
Antithrombin III Activity
Activated Protein C-Resistance


Preferred Specimen
5 mL frozen platelet-poor citrated plasma collected in a 3.2% sodium citrate (light-blue-top) tube


Minimum Volume
2.5 mL


Instructions
Platelet-poor plasma: Centrifuge light blue-top tube for 15 minutes at approximately 1500 g within 60 minutes of collection. Using a plastic pipette, remove plasma, taking care to avoid the WBC/platelet buffy layer and place into a plastic vial. Centrifuge a second time and transfer platelet-poor plasma into a new plastic vial. Plasma must be free of platelets (<10,000/mcL) Freeze immediately and ship on dry ice.


Transport Temperature
Frozen


Specimen Stability
Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 14 days


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
See individual assays


Methodology
Clotting Assay • Clot Detection • Chromogenic Substrate • RVVT-based Assay (Clot-based)

Setup Schedule
Set up and Report available: See individual assays


Limitations
Protein C, Activity: Expected impact by therapeutic levels (potential interference depends upon drug concentration): Warfarin: decrease; Heparin (UFH or LMWH): UFH-no effect, LMWH-may falsely increase at higher levels; Dabigatran or Argatroban (Thrombin Inhibitors): may falsely increase; Rivaroxaban or Apixaban (Factor Xa Inhibitors): may falsely increase.
Protein S, Activity: Expected impact by therapeutic levels (potential interference depends upon drug concentration): Warfarin: decrease; Heparin (UFH or LMWH): may falsely increase at values approximately greater than 1.0 IU/mL; Dabigatran or Argatroban (Thrombin Inhibitors): may falsely increase; Rivaroxaban or Apixaban (Factor Xa Inhibitors): no effect.
Antithrombin III Activity: Expected impact by therapeutic levels (potential interference depends upon drug concentration): Warfarin: no effect; Heparin (UFH or LMWH): no effect to decrease (UFH may decrease levels physiologically but no assay interference); Dabigatran or Argatroban (Thrombin Inhibitors): may falsely increase; Rivaroxaban or Apixaban (Factor Xa Inhibitors): no effect.
Activated Protein C Resistance: Expected impact by therapeutic levels (potential interference depends upon drug concentration): Warfarin: no effect; Heparin (UFH or LMWH): no effect; Dabigatran or Argatroban (Thrombin Inhibitors): unable to obtain assay endpoint; Rivaroxaban or Apixaban (Factor Xa Inhibitors): no effect.


Clinical Significance
This panel is useful to determine the etiology of various hypercoagulability states.




The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.