Protein C and S Activity with Reflex to Protein C and/or S Antigen
Quest Diagnostics
Sample type: Plasma
Requires fasting: No
Phlebotomy required
Details
Protein C and S Activity with Reflex to Protein C and/or S Antigen - Aids in characterization of protein C (PC) and/or protein S (PS) deficiency. PC and PS deficiency is associated with increased thrombotic risk and may be congenital or acquired. Acquired PC and PS deficiency may occur with vitamin K antagonists/deficiency, liver disease, malignancy, consumptive DIC, surgery, trauma, and hepatic immaturity of the newborn. In addition, PS deficiency is physiologic in pregnancy.
Reflex testing uses predefined clinical logic to automatically order one or more follow-up tests based on the initial test results. Reflex tests are performed automatically without the intervention of the ordering practitioner. They are conducted using the same sample your Patient already provided. If reflex tests are required, there will be additional charges.
Initial test
- Protein C, Activity
- Protein S, Activity
Possible reflex biomarkers
- Protein C, Antigen
- Protein S Antigen, Total
Estimated days for results: Results should be available within 2 - 5 business days after samples are received at the lab.
Protein C and S Activity with Reflex to Protein C and/or S Antigen - Aids in characterization of protein C (PC) and/or protein S (PS) deficiency. PC and PS deficiency is associated with increased thrombotic risk and may be congenital or acquired. Acquired PC and PS deficiency may occur with vitamin K antagonists/deficiency, liver disease, malignancy, consumptive DIC, surgery, trauma, and hepatic immaturity of the newborn. In addition, PS deficiency is physiologic in pregnancy.
Expected impact by therapeutic levels (potential interference depends upon drug concentration):
- Warfarin: decrease
- Heparin (UFH or LMWH): no effect to falsely increased activity levels at higher levels
- Dabigatran or Argatroban (Thrombin Inhibitors): may falsely increase activity
- Rivaroxaban, Apixaban, Edoxaban (Factor Xa Inhibitors): may falsely increase activity
2–5 business days
Protein C Activity
0-15 years No reference range available
≥16 years 70-180 % normal
Protein S Activity
Male 70-150 % normal
Female 60-140 % normal
Blood Draw Options with Fullscript
Fullscript offers several convenient phlebotomy options to complete your lab testing:
Quest Diagnostics Patient Service Centers (PSC)
- Location: Visit a nearby Quest Diagnostics Patient Service Center.
- Cost: $10 sample collection fee (paid during lab order checkout).
- Scheduling: Schedule your appointment here. Appointments are recommended to reduce wait times. Walk-ins are accepted, but may experience delays. Aim to arrive 10 minutes before your appointment.
- Collection Instructions:
- Bring a valid ID.
- Bring your digital or printed requisition form, available in the Labs tab of your Fullscript account.
- Check-in: Scan the QR code from your confirmation email or follow kiosk instructions.
- More Info: Quest Diagnostics blood draw guide
Getlabs Mobile Phlebotomy
- Location: Sample collection at your home or office.
- Cost: $85 sample collection fee (paid during lab order checkout).
- Availability: Available in most locations – enter your ZIP code during checkout to confirm.
- Scheduling: Schedule your appointment here through your Fullscript account.
- Collection Instructions:
- Have your digital or printed requisition form and valid ID ready.
- Your phlebotomist will contact you by phone to coordinate arrival.
- More Info: Getlabs blood draw guide
- Preferred Specimen(s): 2 mL (x2) frozen plasma collected in 3.2% sodium citrate (light blue-top) tubes
- Alternative: NA
- Minimum Volume: 1 mL
- Collection Instructions: NA
- Transport Container: Transport tube
- Transport Temperature: Frozen
- Specimen Stability:
- Frozen: 14 days
- Reject Criteria:
- Gross hemolysis
State restrictions:
Patient can't order this test if they are located in Puerto Rico, Hawaii, Rhode Island, New Jersey, or New York
