Test Code 521193133 TSH w/ Reflex to FT4
Performing Laboratory
Torrance Memorial Laboratories
Testing Algorithm
TSH will be performed. If results are out of reference range, Free T4 will be added at an additional charge.
Specimen Requirements
Submit only 1 of the following specimens:
Hospital Preferred Specimen Type: Plasma
Container/Tube: Lithium heparin gel
Outreach Preferred Specimen Type: Serum
Container/Tube: Serum gel
Spin Instructions:
Serum gel: Allow to sit for 30 minutes prior to spinning. Spin within 2 hours of collection.
Heparin plasma: Spin within 45 minutes of collection.
Also acceptable: Red top tube
Specimen Transport Temperature
Ambient
Storage Temp Stability
Room Temperature: 24 hours
Refrigerated: 7 days
Methodology
LOCI—Luminescent Oxygen Channeling Immunoassay
Reference Range
TSH:
1 - 23 months: 0.816 – 5.91 uIU/mL
2 - 12 years: 0.662 – 3.90 uIU/mL
13 – 20 years: 0.463 – 3.98 uIU/mL
> 20 years: 0.350 – 4.940 uIU/mL
Reference range change as of 6/22/2021
See Free T4 listing for those reference ranges
Day(s) Test Set Up/TAT
Performed:
Daily
Available STAT
STAT: < 1 hr
Routine: < 4 hrs
Aliases
Thyroid Stimulating Hormone w/reflex
CPT Code
84443 (TSH)
84439 (Free T4) if needed
*Additional codes/fees may apply*