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Test Code 64470569 FT4 (Thyroxine, Free)

Performing Laboratory

Torrance Memorial Laboratories

Specimen Requirements

Submit only 1 of the following specimens:

 

Hospital Preferred Specimen Type: Plasma

Container/Tube: Lithium heparin gel

 

Outreach Preferred Specimen Type: Serum

Container/Tube: Serum gel

 

Spin Instructions:

Serum gel:  Allow to sit for 30 minutes prior to spinning.  Spin within 2 hours of collection.

Heparin plasma: Spin within 45 minutes of collection.   

Also acceptable:  Red top tube

Specimen Transport Temperature

Ambient

 

Storage Temp Stability: Serum
Room Temperature: 24 hours
Refrigerated Temperature: 5 days

 

Methodology

Chemiluminescent Microparticle Immunoassay

Reference Range

Neonate - 1 month:  0.90 - 2.30 ng/dL

 

1 month - 1 year:  0.90 - 1.80 ng/dL

 

1 - 6 years:  0.90 - 1.60 ng/dL

 

6 - 10 years:  0.90 - 1.50 ng/dL

 

10 - 18 years:  0.80 - 1.50 ng/dL 

 

18 years and up:  0.70 – 1.48 ng/dL

 

*Note: Reference ranges provided on this web site are for guidance only, and may not reflect the most recent changes. Refer to laboratory reports for current data.   

Day(s) Test Set up/TAT

Performed:

Daily

Available STAT

TAT:

STAT: <1 hr

Routine: < 4 hrs

Aliases

FT4, Free T4

CPT Code

84439