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Test Code PROTSI Protein S Antigen (Free), No Coumadin

Specimen Requirements

Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
*Platelet Poor Plasma 3.2% Citrated Blue Top Tube (BTT)   0.75 mL 0.75 mL 0.5 mL

Collection/Processing Instructions

One 0.75 mL citrated Blue Top Tube (BTT) plasma aliquot. (If more than one coagulation test is ordered, a separate aliquot is needed for each test.)

 

  • Collect in Citrated Blue Top Tube (BTT)
  • Citrate anticoagulant must be adjusted for HCT >55%
  • Tube must be at least 90% full
  • Invert completely 3-4 times (without shaking) to mix


*See Instructions for: Preparation of Platelet Poor Plasma

Specimen Stability Information

Specimen Type Temperature Time
Plasma Frozen 6 months

Rejection Criteria

Clotted or Hemolyzed
Contamination with IV or Hickman Line fluids
Specimens that thaw during storage or transport

Test Information

Free Protein S Antigen will be performed.

Do not order if the patient has received Coumadin for the past two weeks. If patient is on a stable dose of Coumadin (2 weeks), see Protein S Antigen, On Coumadin test (PROT-SM).

Free Protein S Antigen is the initial test in the algorithm for the diagnosis of Protein S deficiency. This assay has better accuracy and less potential interference that Protein S Activity.

When indicated, Protein S Activity testing will be initiated by a clinical pathologist who has reviewed the case.

 
See Clinical Practice Guidelines:Hypercoagulability for more information

Reference Range Information

Performing Location Reference Range
Marshfield Free: 55-146 %

Marshfield Labs Performing Department

Marshfield Labs Hematology

Performing Information

Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
Marshfield Monday and Thursday Less than 2 hours Immuno-turbidimetric /IL ACL TOP 550

CPT Codes

CPT Modifier
(if needed)
Quantity Description Comments
85306     Protein S, Free  

Outreach CPT Codes

CPT Modifier
(if needed)
Quantity Description Comments
85306     Protein S, Free  

Ordering Applications

Ordering Application Description
Centricity Protein S Ag-No Coumadin
Cerner Protein S Total-NO Coumadin
COM Protein S Ag-No Coumadin