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Prekallikrein Assay

Prekallikrein (Fletcher Factor) Assay

Test Codes

EPIC: LAB6321, Beaker: XPREK, ARUP: 0099043

Department

Send Outs

Specimen Collection Criteria

Collect: Two Light Blue-top Sodium Citrate tubes.

TUBES MUST BE FULL.

Physician Office/Draw Specimen Preparation

For optimal results, maintain whole blood specimen at room temperature (20-26°C or 68-78.8°F) prior to transport. Transport whole blood to the Laboratory within 4 hours of collection. If transport within 4 hours is not possible, the following procedure must be followed for accurate results:

1. Centrifuge the capped tubes at 1500 x g for 15 minutes.
2. Transfer plasma with plastic pipette into a plastic polypropylene centrifuge tube, cap and centrifuge an additional 15 minutes at 1500 x g to obtain platelet poor plasma (PPP) which has a platelet count less than 10.0 bil/L. Plasma with a platelet count of less than 10.0 bil/L is critical for accurate results.
3. Immediately remove only the top two-thirds of the PPP and transfer into a plastic aliquot tube.
4. Freeze (-20°C/-4°F or below) the PPP aliquot immediately.
5. Transport frozen on DRY ICE. Specimen must remain frozen during transport.

Preparation for Courier Transport

Transport: 2.0 mL PPP, frozen (-20°C/-4°F or below). (Minimum: 1.0 mL)

Rejection Criteria

Specimens not collected and processed as indicated.

In-Lab Processing

For optimal results, maintain whole blood specimen at room temperature (20-26°C or 68-78.8°F) prior to transport. Transport whole blood to the Laboratory within 4 hours of collection. If transport within 4 hours is not possible, the following procedure must be followed for accurate results:

1. Centrifuge the capped tubes at 1500 x g for 15 minutes.
2. Transfer plasma with plastic pipette into a plastic polypropylene centrifuge tube, cap and centrifuge an additional 15 minutes at 1500 x g to obtain platelet poor plasma (PPP) which has a platelet count less than 10.0 bil/L. Plasma with a platelet count of less than 10.0 bil/L is critical for accurate results.
3. Immediately remove only the top two-thirds of the PPP and transfer into a plastic aliquot tube.
4. Freeze (-20°C/-4°F or below) the PPP aliquot immediately.
5. Transport frozen on DRY ICE. Specimen must remain frozen during transport.

Transport: 2.0 mL PPP, frozen (-20°C/-4°F or below). (Minimum: 1.0 mL)

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 4 hours
Refrigerated (2-8°C or 36-46°F): unacceptable
Frozen (-20°C/-4°F or below): 14 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.

Laboratory

Sent to ARUP Laboratory in Salt Lake City, UT.

Performed

Tuesday.
Results available in 2-9 days.

Reference Range

By Report.

Test Methodology

Electromagnetic Mechanical Clot Detection

CPT Codes

85292

Contacts

Last Updated

10/8/2023