Yale New Haven Hospital

Department of Laboratory Medicine
Test Directory

[ Test Name Index ]

[ Home & References ]

Thyroxine, free, by equilibrium dialysis

Lab Section: 

Sendout Reference

 

Lab Location: 

Sendout

Reference Lab: 

Quest

 

Test ID: 

LAB3542

 

Methodology: 

Direct Equilibrium Dialysis • Immunoassay (IA)

Schedule: 

Daily

Reported: 

5 days

Specimen Requirements: 

Collection: 3.0 mL Blood in a Gold Top Tube.
Pediatric volume: 1 mL.
Fasting is preferred. Please specify on the request form the patient s age.
Transport: Room temperature.
Stability: Ambient or Refrigerated: 7 days; Frozen 28 days

 

Notes: 

Clinical Indications: Free T4 by equilibrium dialysis is the most accurate measure of Free T4. Results are independent of the concentration of the T4-binding proteins, the presence of molecular variants of these proteins, or circulating autoantibodies. Free T4 is useful in distinguishing euthyroidism from thyroid disease.

Performing laboratory: Quest Diagnostics Nichols Institute 14225 Newbrook Drive Chantilly, VA 20153

Reference Interval: 

See patient report or consult reference laboratory website.

http://www.questdiagnostics.com/testcenter/TestDetail.action?tabName=OrderingInfo&ntc=35167

CPT Code(s): 

84439

Last Changed: 

12/15/2016 14:13:53

Last Reviewed: 

8/16/2017 6:01:36