Protein C, Total Antigen
Also known as: PROT C
Use
The test is used to subtype deficiency in known protein C-deficient individuals. It is not recommended for detecting protein C deficiency; the preferred test for detection is Protein C, Functional (0030113). It is important that patients are not on warfarin therapy for two weeks prior to testing as warfarin may decrease protein C values, leading to inaccurate measurements.
Special Instructions
Order the test only when the patient is not on warfarin therapy for at least two weeks prior to testing. This ensures accurate measurement of protein C levels. It is critical to use a light blue sodium citrate collection tube.
Limitations
This test is not recommended for detecting protein C deficiency as it may not accurately reflect deficiency levels in patients. Warfarin therapy can significantly affect the test results, producing decreased protein C values. Patients should be off warfarin therapy for at least two to four weeks before the test to avoid inaccuracies.
New York Approved
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 27820-0
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
2 mL
Minimum Volume
1 mL
Container
ARUP standard transport tube
Collection Instructions
Collect using a light blue (sodium citrate) tube. Transfer 2 mL of platelet-poor plasma to the ARUP standard transport tube.
Storage Instructions
Transport frozen. CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.
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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