Protein C Antigen

Preferred Specimen(s) Platelet-poor 3.2% citrate anticoagulated plasma collected in (light blue-top) tube

Instructions Draw blood in (light blue-top) tube containing 3.2% sodium citrate, mix gently by inverting 3-4 times. Centrifuge 15 minutes at 1500 RCF (relative centrifugal force). 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. Freeze immediately and transport on dry ice.

Transport Container Plastic screw-cap vial

Transport Temperature Frozen

Reject Criteria

  • Received room temperature
  • Received refrigerated
  • Received thawed

Methodology Enzyme immunoassay

Clinical Significance Aids in diagnosis of congenital deficiencies characterized by recurrent venous thrombosis. Acquired deficiencies associated with Protein C include: oral anticoagulant therapy, liver disease, vitamin K deficiency, malignancy, consumptive DIC, surgery, trauma, antibodies

to Protein C and hepatic immaturity of the newborn.