Protein C, Functional
Label Mnemonic: | PCFX |
Epic code: | LAB1133 |
Order form: | Laboratory Requisition |
Supply order: | Supply Order Form |
Billing: | Billing Policies |
CPT code: | 85303 |
Specimen(s):
Plasma
More information
Collection Medium:
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Light Blue top tube 2.7 mL (Na Citrate) |
Minimum:
Full draw; 2.7 mL light blue top
Rejection Criteria:
Short drawn tube, clot, traumatic tap (excessive hemolysis).
Testing Schedule:
0800-1630 Monday, Wednesday and Friday. If you need results STAT,
call Hematology resident (0800-1630, M-F) at 356-8628. All other
times page the Pathology resident on-call at 3404.
Turn Around Time:
1-3 days upon receipt in laboratory
Reference Range:
>=83%
Interpretive Data:
Patients on warfarin may have decreased protein C levels. Warfarin
therapy should be discontinued for at least two weeks prior to
protein C testing. Decreased concentrations of protein C are also
associated with liver disease, vitamin K deficiency, acute
thrombosis, and DIC. Increased protein C concentrations may be
observed in nephrotic syndrome, pregnancy, and with estrogen
therapy.
Reference range updated 9/22/2020.
Reference range updated 9/22/2020.
Methodology:
Activity detection by chromogenic substrate.
Sample Processing:
Double-centrifuge specimen to prepare platelet-free plasma.
Immediately centrifuge specimen at 3500 RPM for 12 minutes.
Using a plastic transfer pipette, carefully remove plasma from cells avoiding the platelet/buffy coat.
Place plasma into a labeled plastic tube.
Centrifuge plasma again at 3500 RPM for 12 minutes.
Remove the top of the plasma and place into a labeled plastic tube.
Freeze double-spun plasma within 4 hours of collection time at -20 degrees C or below.
Immediately centrifuge specimen at 3500 RPM for 12 minutes.
Using a plastic transfer pipette, carefully remove plasma from cells avoiding the platelet/buffy coat.
Place plasma into a labeled plastic tube.
Centrifuge plasma again at 3500 RPM for 12 minutes.
Remove the top of the plasma and place into a labeled plastic tube.
Freeze double-spun plasma within 4 hours of collection time at -20 degrees C or below.
Sample Storage:
Freeze specimen immediately.
Transport Instructions:
Place labeled specimen into zip-lock type biohazard bag; seal
bag.
Place packing list into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container.
Samples received thawed will be cancelled.
Place packing list into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container.
Samples received thawed will be cancelled.