Protein C Activity, Plasma
Use
This test is used as an initial investigation for evaluating patients suspected of having congenital protein C deficiency, such as those with a personal or family history of thrombotic episodes. It helps in detecting and confirming congenital type I and type II protein C deficiencies, including homozygous deficiency. Additionally, the test aids in identifying decreased functional protein C of acquired causes like oral anticoagulant effects, vitamin K deficiency, liver disease, and intravascular coagulation and fibrinolysis/disseminated intravascular coagulation.
Special Instructions
Not provided.
Limitations
Protein C activity measurements may be affected by the presence of Heparin (≥2 U/mL), Hemoglobin (>500 mg/dL), Bilirubin (>21 mg/dL), and Triglycerides (>890 mg/dL). Lipemia can also interfere with assay results. Samples should ideally be drawn in a fasting state to avoid erroneous outcomes. Furthermore, this chromogenic assay may not detect certain congenital protein C variants identifiable with clot-based functional assays.
New York Approved
Methodology
Chromogenic
Biomarkers
Protein C
Protein
LOINC Codes
- 27818-4 - Prot C Act/Nor PPP Chro
- 27818-4 - Prot C Act/Nor PPP Chro
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.5 mL
Container
Polypropylene plastic vial
Collection Instructions
Centrifuge, transfer plasma into a plastic vial, and centrifuge again. Aliquot plasma into a vial leaving 0.25 mL in the original tube. Freeze immediately at -20°C or, ideally, at -40°C or below.
Patient Preparation
Fasting for 8 hours is preferred but not required.
Causes for Rejection
Gross hemolysis, lipemia, or icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 14 days |