Not recommended for routine evaluation of thyroid disorders. Preferred test is Thyroxine, Free (Free FT4) (0070138).
- Patient Preparation
- Collect
- Plain Red or Serum Separator Tube (SST).
- Specimen Preparation
- 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)
- Storage/Transport Temperature
- Refrigerated.
- Unacceptable Conditions
- Plasma.
- Remarks
- Stability
- After separation from cells: Ambient: 4 days; Refrigerated: 2 weeks; Frozen: 1 month
Free Thyroxine ng/dL | ||
---|---|---|
Age | Female | Male |
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 |
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
0093244 | Free T4 by Equil Dialysis-TMS | 6892-4 |
- Direct Dialysis
- FT4
- T4, Free, Equilibrium Dialysis