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Published on November 14, 2016

Thyroid Function Cascade

Includes: TSH, and if indicated - FT4, T3TOT, TPO AB

Tube Type = Gold Top

Tube Type

Test ID LAB5771
EPIC Order
 THYROID FUNCTION CASCADE
CPT Code(s)
84443 (additional CPT codes as indicated- see individual tests)
Group/Individual Test Group
Laboratory Core Laboratory
Tube Station Routine: 30, STAT: 888
Specimen Routine: 7 mL blood/gold SSt tube/red plain tube also acceptable
Micro:
3.0 mL blood/gold SST or red plain tube (do not send micro collection devices)
Stability
Unspun: 4 hrs
Room Temp: 4 hrs 
Refrigerator: 48 hrs
Frozen: 4 weeks 
Availability Routine: 24 hrs/day
STAT: Yes
Turnaround Time 2 hrs (for first result)
Reference Range Normal: See reference ranges for individual tests
Comments
  • The Thyroid Function Cascade is indicated for Non-hospitalized, asymptomatic adults without known or suspected thyroid or pituitary disease.
  • Thyroid Stimulating Hormone is tested initially. Based on the result, a Free T4 and/or Total T3 and/or Thyroid Peroxidase Antibody will be reflexed.

Reviewed by J. Carr on January 02, 2026

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514