Protein C, Functional with Reflex to Protein C, Total and Protein S, Free with Reflex to Protein S, Total
Also known as: PROT C/S R
Use
This test is used to detect and subtype deficiencies in proteins C and S, which are important in regulating blood coagulation. Deficiencies in these proteins can lead to a hypercoagulable state, increasing the risk of thrombosis. Protein C, a vitamin K-dependent serine protease, plays a crucial role in inactivating coagulation factors Va and VIIIa. Protein S acts as a cofactor to Protein C, enhancing its anticoagulant effect. Identifying deficiencies in these proteins helps in diagnosing thrombotic disorders and can guide anticoagulant therapy management strategies.
Special Instructions
Not provided.
Limitations
The test may not be accurate in the presence of anticoagulant therapy such as heparin, direct thrombin inhibitors, or factor Xa inhibitors. It may also not differentiate between inherited and acquired deficiencies of protein C and S. Interpretation of low values should consider potential causes like liver disease, acute thrombosis, or other medical interventions. Repeat testing is recommended if initial low results are acquired under such conditions, after excluding acquired causes.
New York Approved
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 27819-2 - Prot C Act/Nor PPP
- 27821-8 - Prot S Free Ag Act/Nor PPP IA
Result Turnaround Time
1-5 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
4 mL
Minimum Volume
2 mL
Container
ARUP standard transport tube
Collection Instructions
Collect in a lt. blue (sodium citrate) tube. Handle according to standard guidelines for hemostasis/thrombosis specimen collection.
Causes for Rejection
Serum, EDTA plasma, clotted or hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 hours |
| Refrigerated | Unacceptable |
| Frozen | 3 months |
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