Thyroxine
0070140
Ordering Recommendation
Not recommended for routine thyroid screening.
Submit With Order
Mnemonic
T4
Methodology
Quantitative Electrochemiluminescent Immunoassay
Performed
Sun-Sat
Reported
Within 24 hours
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
 
Collect
Serum separator tube or plasma separator tube. Also acceptable: Lavender (EDTA).  
Specimen Preparation
Allow specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
Grossly hemolyzed specimens.  
Remarks
 
Stability
After separation from cells: Ambient: 24 hours; Refrigerated: 1 week; Frozen: 1 month  
Reference Interval
Cord blood 6.60-​17.50 µg/dL
0-​3 days 5.37-​22.40 µg/dL
4-​30 days 5.24-​23.20 µg/dL
1-​23 months 5.37-​16.00 µg/dL
2-​6 years 5.26-​14.80 µg/dL
7-​11 years 5.70-​14.10 µg/dL
12-​19 years 4.74-​14.60 µg/dL
20 years and older 5.10-​14.10 µg/dL
Interpretive Data
Note
CPT Code(s)
84436
Components
Component Test Code*Component Chart Name
0070140Thyroxine
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Cross References
  • Syn-Thyroid
  • T4
  • T4 Total Only, T4, Serum
  • Tetraiodothyronine
  • Thyroid Hormone
  • Thyroxine (T4)
  • Total T4