Thyroxine, Free by Equilibrium Dialysis
Label Mnemonic: FT4D
Epic Lab Code: LAB3177
Commercial Mail-out Laboratory
5231 RCP
356-8593
Specimen(s):
Serum
Specimen Instructions:
Separate from cells or gel ASAP or within 2 hours of collection.
Collection Medium:
Red top tube 5 mL (Clot Activator)
Minimum:
Preferred Minimum: 2 mL serum
Absolute Minimum: 0.3 mL serum
Rejection Criteria:
Serum separator tubes and gels.
Turn Around Time:
2-5 days upon receipt at reference laboratory
Reference Range:
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
Methodology:
Quantitative Equilibrium Dialysis/High Performance Liquid Chromatography-Tandem Mass Spectrometry
CPT Code:
84439