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Labcorp Oklahoma, Inc.
Test Directory


Index:

Protein S Antigen, Free and Total

Order Name PROT S FT AG
Test Number: 5194331
Revision Date 12/12/2022
Test Name Methodology LOINC Code
Protein S Antigen, Free and Total
See Test Notes  
SPECIMEN REQUIREMENTS
Specimen Specimen Volume (min) Specimen Type Specimen Container Transport Environment
Preferred 1 mL Plasma Sodium Citrate 3.2% (Blue Top) Frozen
Instructions Specimen Type: Blue-top (sodium citrate) tube
Specimen Storage: Freeze
Specimen Collection: CITRATED PLASMA SAMPLES SHOULD BE COLLECTED BY DOUBLE CENTRIFUGATION. 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 anti- coagulant with the blood. A discard tube is not required prior to collection of coagulation samples except when using a winged blood collection device (i.e. 'butterfly'), in which case a discard tube should be used.[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 alternate 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. Centrifuge for 10 minutes and carefully remove 2/3 of the plasma using a plastic transfer pipette, being careful not to disturb the cells. Deliver to a plastic transport tube, cap, and recentifuge for 10 minutes. Use a second plastic pipette to remove plasma, staying clear of the platelets at the bottom of the tube. Transfer the plasma into a LabCorp PP transpak frozen purple tube with screw cap (LabCorp 49482). FREEZE immediately and maintain frozen until tested. Please print and use the Volume Guide for Coagulation Testing to ensure proper draw volume. Please print and use the Volume Guide for Coagulation Testing to ensure proper draw volume.
Special Instructions: If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted. Refer to Coagulation Collection Procedures for directions.
Specimen Stability: Ambient: Not Available, Refrigerated : Not Available, Frozen: Not Available
GENERAL INFORMATION
Expected TAT 2 - 3 days  
Performing Labcorp Test Code 164517 
Notes Total and Free PS antigens are measured by latex immunoassay Free PS is measured by EIA after C4b-BP complexed PS is precipitated out with polyethylene glycol.
Labcorp Test Code: 164517
CPT Code(s) 85306, 85305
Lab Section Reference Lab