Protein C Activity
Test Code
Clinical Significance
Protein C Activity - Protein C (PC) deficiency may be congenital or acquired and is associated with venous thrombosis. Acquired PC deficiency may occur with vitamin K antagonists/deficiency, liver disease, malignancy, consumptive DIC, surgery, trauma, and hepatic immaturity of the newborn.
Anticoagulant interference: Expected impact by therapeutic levels (potential interference depends upon drug concentration): Vitamin K antagonists (eg warfarin): decrease; Heparin (UFH or LMWH): no effect to falsely increased activity levels at higher levels; Dabigatran or Argatroban (Thrombin Inhibitors): may falsely increase activity; Rivaroxaban, Apixaban, Edoxaban (Factor Xa Inhibitors): may falsely increase activity.
Test Resources
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Test Details
Methodology
Reference Range(s)
| 0-15 years | No reference range available |
| ≥16 years | 70-180 % normal |
Alternative Name(s)
Preferred Specimen(s)
1 mL frozen platelet-poor plasma collected in 3.2% sodium citrate (light blue-top) tube
Minimum Volume
0.5 mL
Collection 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 transport tube. Plasma must be free of platelets (<10,000/mcl). Freeze immediately and ship on dry ice.
Transport Container
Transport tube
Transport Temperature
Frozen
Specimen Stability
- Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 14 days
Reject Criteria
Gross hemolysis • Received thawed
Setup Schedule
Refrigerated: Unacceptable
Frozen: 14 days