PROTEIN C ANTIGEN
General Information
HLAB/HOL Code: PRCAG
UPHSM LIS Test #: 025670
Schedule:
Testing Time: 2-4 Days
Testing Lab: Labcorp
UPHSM LIS Test #: 025670
Schedule:
Testing Time: 2-4 Days
Testing Lab: Labcorp
Specimen Info
Only 1 specimen type required, unless otherwise specified
Volume: 2.0(1.0) mL Plasma Na Cit
Temperature: Frozen
Tube Type: Platelet Poor Plasma (sodium citrate)
Collection Info:
If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted
Collection: Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate.1 Evacuated collection tubes must be filled to completion to ensure a proper blood-to-anticoagulant ratio.2,3 The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood. A discard tube is not required prior to collection of coagulation samples, except when the sample is collected using a winged (ie, "butterfly") collection system. With a winged blood collection set a discard tube should be drawn first to account for the dead space of the tubing and prevent underfilling of the evacuated tube.4,5 When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes. Any tube containing an alternative anticoagulant should be collected after the blue-top tube. Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes. Please print and use the Volume Guide for Coagulation Testing to ensure proper draw volume.
Temperature: Frozen
Tube Type: Platelet Poor Plasma (sodium citrate)
Collection Info:
If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted
Collection: Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate.1 Evacuated collection tubes must be filled to completion to ensure a proper blood-to-anticoagulant ratio.2,3 The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood. A discard tube is not required prior to collection of coagulation samples, except when the sample is collected using a winged (ie, "butterfly") collection system. With a winged blood collection set a discard tube should be drawn first to account for the dead space of the tubing and prevent underfilling of the evacuated tube.4,5 When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes. Any tube containing an alternative anticoagulant should be collected after the blue-top tube. Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes. Please print and use the Volume Guide for Coagulation Testing to ensure proper draw volume.
Specimen Acceptability
Cause for Rejection:
Gross hemolysis; clotted specimens; frozen specimens thawed in transit; inadequate labeling.
Gross hemolysis; clotted specimens; frozen specimens thawed in transit; inadequate labeling.
Methods
Enzyme immunoassay (EIA)
Clinical Utilities
Use: Confirmation and characterization of protein C deficiency
Limitations: Individuals with heterozygous PC deficiency may have low normal PC levels.7 Treatment with warfarin decreases the levels of vitamin K-dependent factors including PC. PC levels start to drop after six hours of warfarin treatment and do not regain pretreatment levels until generally two weeks after cessation of therapy. PC levels can become depleted as the result of activation of coagulation, limiting the utility of testing for congenital PC deficiency during the immediate convalescent period after a thrombotic event.7
This procedure may be considered by Medicare and other carriers as investigational and, therefore, may not be payable as a covered benefit for patients.
Limitations: Individuals with heterozygous PC deficiency may have low normal PC levels.7 Treatment with warfarin decreases the levels of vitamin K-dependent factors including PC. PC levels start to drop after six hours of warfarin treatment and do not regain pretreatment levels until generally two weeks after cessation of therapy. PC levels can become depleted as the result of activation of coagulation, limiting the utility of testing for congenital PC deficiency during the immediate convalescent period after a thrombotic event.7
This procedure may be considered by Medicare and other carriers as investigational and, therefore, may not be payable as a covered benefit for patients.
CPT Codes
85302
* The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding
is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.
