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T4 Free, Direct Dialysis

Order Code: T4FREE

Test Summary

For the differential diagnosis of euthyroid hyperthyroxinemia from hyperthyroidism or for the differential diagnosis of euthyroid hypothyroxinemia from hypothyroidism.

Aliases

  • N/A

Specimen Collection

Order Code

T4FREE

EPIC (Premier) Code

LAB3829

Includes

N/A

CPT Code

  • 84439

Billing Code

  • 670706

CPT Statement

Methodology

Equilibrium Dialysis • Chromatography/Mass Spectrometry

FDA Status

This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. The FDA has determined that such clearance or approval is not necessary. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Physician Attestation of Informed Consent

N/A

Testing Laboratory

Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly VA, 20153

Department

Reference Testing

Reference Range

Adult0.9-2.2 ng/dL
   
Prematures, 25-30 Weeks
  Birth-7 Days0.5-3.3 ng/dL
Prematures, 31-36 Weeks
  Birth-7 Days1.3-4.7 ng/dL
Cord Blood, >37 Weeks1.2-2.2 ng/dL
Birth-4 Days2.2-5.3 ng/dL
2 Months-2 Years1.2-2.5 ng/dL
3 Years-17 Years1.0-2.4 ng/dL
   
Pregnancy
  First Trimester0.9-2.0 ng/dL
  Second Trimester0.8-1.5 ng/dL
  Third Trimester0.8-1.7 ng/dL

Setup Schedule / Expected Turnaround Time

Monday - Saturday; Report available: 3 - 4 days

Specimen Collection

Billing

CPT Code

  • 84439

Billing Code

  • 670706

CPT Statement

Result Information

Methodology

Equilibrium Dialysis • Chromatography/Mass Spectrometry

Testing Laboratory

N/A

Reference Range

Adult0.9-2.2 ng/dL
   
Prematures, 25-30 Weeks
  Birth-7 Days0.5-3.3 ng/dL
Prematures, 31-36 Weeks
  Birth-7 Days1.3-4.7 ng/dL
Cord Blood, >37 Weeks1.2-2.2 ng/dL
Birth-4 Days2.2-5.3 ng/dL
2 Months-2 Years1.2-2.5 ng/dL
3 Years-17 Years1.0-2.4 ng/dL
   
Pregnancy
  First Trimester0.9-2.0 ng/dL
  Second Trimester0.8-1.5 ng/dL
  Third Trimester0.8-1.7 ng/dL

Setup Schedule / Expected Turnaround Time

Monday - Saturday; Report available: 3 - 4 days