Lab Test

Free T4 (Thyroxine) by Equilibrium Dialysis

This test is subject to pathology approval prior to sending to the reference laboratory for testing., ARUP #93244, Order as a Miscellaneous Sendout.

Test Codes

ARUP #93244, Order as a Miscellaneous Sendout.

Instructions

This test is only available to Endocrinologists and Nuclear Medicine Physicians.

Specimen Collection Criteria

Collect (preferred specimen): One Gold-top SST tube.
Also acceptable: one Red top tube.

Physician Office/Draw Specimen Preparation

Centrifuge to separate serum from cells. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).

Preparation for Courier Transport

Transport: 2.0 mL serum, refrigerated (2-8°C or 36-46°F). (Min: 0.3 mL)

Rejection Criteria

  • Specimens not collected and processed as indicated.

In-Lab Processing

Centrifuge to separate serum from cells. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).

Transport: 2.0 mL serum, refrigerated (2-8°C or 36-46°F). (Min: 0.3 mL)

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 4 days
Refrigerated (2-8°C or 36-46°F): 2 weeks
Frozen (-20°C/-4°F or below): 1 month

Specimen Storage in Department Prior to Disposal:

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

Laboratory

Sent to ARUP Laboratories, Salt Lake City, UT.

Performed

Sunday, Tuesday, Thursday.
Results available in 2-7 days.

Reference Range

By Report.

Test Methodology

High Performance Liquid Chromatography-Tandem Mass Spectrometry.

Interpretation

By Report.

CPT Codes

84432.

Contacts

Last Updated

10/23/2019

Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.

 

This directory currently reflects information only for specimens collected and/or processed at the
Farmington Hills, Grosse Pointe, Royal Oak, and Troy campuses.