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Lab Manual for Moffitt-Long and Mount Zion

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Protein C, Antigen

Item Value
Available Stat? No
Test code PRCI
Test group Protein C
Performed by Quest
Sendout? Yes
Method Enzyme Immunoassay
Collection Instructions 1. Check the expiration date on the label of the blue top vacutainer before drawing the patient.

2. For blood collection in a sodium citrate blue top, the tube must be filled to above the Minimum Fill Indicator on the tube. It is crucial to wait and allow the tube to stop filling before removing it from the needle.

3. With use of a butterfly needle, draw about 1 cc using a separate blue top to remove air from tubing, discard the first tube and then draw a second blue top tube filled to the full extent of the vacuum.

4. Tubes should not be filled past the Maximum Fill dashed line by either using a syringe or removing the tube cap.

If "Protein C" is requested without further specification a protein C activity will be performed.
Container type Blue top filled to full extent of vacuum
Amount to Collect 2.7 mL blood
Sample type Citrated plasma
Preferred volume 1 mL plasma
Min. Volume 0.5 mL plasma
UCSF Rejection Criteria Samples collected in outdated blue top vacutainer. Over-filled or under-filled tubes may be rejected
Processing notes Deliver sample to Hematology ASAP for processing.

Freeze plasma in 1 mL aliquots at -20C. Ship on dry ice Monday-Friday to Quest, test code 4948.

For B &T patients ship on dry ice to LabCorp, test # 080465.

If "Protein C" is requested without further specification, a Protein C activity (PRC) should be ordered.
Units %
Normal range
0-1 day 17-53%
2-5 days 20-64%
6-30 days 21-65%
31-90 days 28-80%
91-180 days 37-81%


≥ 18 year olds 70-140%
Turn around times 4-8 days
Additional information The pediatric reference ranges are from Andrew M et al. Blood. 1987, 70:165. Adult ranges from Quest lab manual.
CPT coding 85302-90
LOINC code 27820-0
Last Updated 7/8/2013 12:33:51 PM
Entry Number 794
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