Not recommended for routine evaluation of thyroid disorders. Preferred test is Thyroxine, Free (Free FT4) (0070138).
Quantitative Equilibrium Dialysis/High Performance Liquid Chromatography-Tandem Mass Spectrometry
Sun, Tue, Thu
Plain Red or Serum Separator Tube (SST).
Separate from cells or gel ASAP or within 2 hours of collection. Transfer 2 mL serum to an ARUP Standard Transport Tube. (Min: 0.3 mL)
After separation from cells: Ambient: 4 days; Refrigerated: 2 weeks; Frozen: 1 month
Effective May 16, 2011
|Free Thyroxine ng/dL|
|25-30 weeks gestation||0.5-3.3 ng/dL||0.5-3.3 ng/dL|
|31-36 weeks gestation||1.3-4.7 ng/dL||1.3-4.7 ng/dL|
|Birth to 1 week||2.2-5.3 ng/dL||2.2-5.3 ng/dL|
|2-3 weeks||0.9-4.0 ng/dL||0.9-4.0 ng/dL|
|1-5 months||1.1-2.2 ng/dL||1.1-2.2 ng/dL|
|6 months-6 years||1.4-2.7 ng/dL||1.4-2.7 ng/dL|
|7 years-17 years||1.1-2.0 ng/dL||1.1-2.0 ng/dL|
|18 years and older||1.1-2.4 ng/dL||1.1-2.4 ng/dL|
|Pregnancy, 1st Trimester||0.7-2.0 ng/dL|
|Pregnancy, 2nd Trimester||0.7-2.1 ng/dL|
|Pregnancy, 3rd Trimester||0.5-1.6 ng/dL|
Compliance Statement B: For laboratory developed tests not using a RUO kit, and for FDA approved, cleared or 510(k) exempt assays with alterations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.
|Component Test Code*||Component Chart Name||LOINC|
|0093244||Free T4 by Equil Dialysis-TMS||6892-4|
- Direct Dialysis
- T4, Free, Equilibrium Dialysis