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Test Code
PSTAG
Test Name
Protein S, Total Antigen
CPT Codes
85305
Expected Turnaround Time
Varies
Specimen and Container Info

Specimen Type: Citrated Platelet-Poor Plasma

  

Collection Container: Light Blue Top (Sodium Citrate)

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect a light blue top (sodium citrate) tube via venipuncture.
  2.  When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes.
  3. Any tube containing an alternate anticoagulant should be collected after the blue-top tube.
  4. Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes.
Processing and Submission Instructions

Platelet-Poor Plasma Processing Instructions

  1. Perform platelet poor plasma processing procedure
  2. Transfer 1 mL of platelet poor plasma to a LabCorp PP transpak frozen purple tube. Freeze immediately.
Patient Preparation

Avoid warfarin (Coumadin®) therapy for two weeks and heparin therapy for two days prior to the test. Do not draw from an arm with a heparin lock or heparinized catheter.
Transport Instructions

Transport to the laboratory frozen. 
Stability Requirements

Frozen

28 days

Freeze/Thaw Cycles

 Stable x3
Causes for Rejection
  • Gross hemolysis
  • Clotted specimen
  • Frozen specimen thawed in transit
  • Improper labeling
Methodology
Immuno Turbidometric
Reference Intervals

 See patient report.
Alternate Names
  •  Protein S, Total
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Varies
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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