Protein C Antigen, Plasma
Use
This test is useful for differentiating congenital type I protein C deficiency from type II deficiency. It helps in evaluating the significance of decreased functional protein C, especially when decreased protein C activity might be congenital rather than acquired, such as due to oral anticoagulant effect, vitamin K deficiency, liver disease, or intravascular coagulation and fibrinolysis/disseminated intravascular coagulation. It is not useful for predicting a thrombotic event.
Special Instructions
Not provided.
Limitations
The test has not been cleared or approved by the US Food and Drug Administration. Platelet contamination may cause spurious results, thus a double-centrifuged specimen is critical for accurate results. Acquired protein C deficiency is of uncertain clinical hemostatic significance, and the clinical significance of increased protein C levels is unknown.
New York Approved
Methodology
Immunoassay (ELISA)
Biomarkers
Protein C
Protein
LOINC Codes
- 27820-0 - Prot C Ag Act/Nor PPP IA
- 27820-0 - Prot C Ag Act/Nor PPP IA
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.5 mL
Container
Light-blue top (3.2% sodium citrate); Submission: Polypropylene plastic vial
Collection Instructions
For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again. Aliquot plasma into a plastic vial leaving 0.25 mL in the bottom of centrifuged vial. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C or ideally, at -40 degrees C or below.
Patient Preparation
Fasting: 8 hours, preferred but not required
Causes for Rejection
Gross hemolysis, gross lipemia
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 2 years |