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Test Code T3 T3 (Triiodothyronine), Total, Serum

Additional Codes

Mayo Test ID COPIA Test Code EPIC Test Codes
T3 T3-T3(Triiodothyronine), Total

LAB0208116

 T3 TOTAL (FORMERLY T3 BY RIA)

 

Reporting Name

T3 (Triiodothyronine), Total, S

Useful For

Second-order testing for hyperthyroidism in patients with low thyroid-stimulating hormone values and normal thyroxine levels

 

Diagnosing triiodothyronine (T3) toxicosis

 

This test is not useful for general screening of the population without clinical suspicion of hyperthyroidism.

Testing Algorithm

For information see Thyroid Function Ordering Algorithm.

Method Name

Electrochemiluminescence Immunoassay

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Specimen Type

Serum


Specimen Required


Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions: Centrifuge and aliquot serum into plastic vial.


Specimen Minimum Volume

0.75 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 7 days
  Frozen  30 days

Reject Due To

Gross hemolysis Reject
Gross lipemia OK
Gross icterus OK

Reference Values

Pediatric

0-5 days: 73-288 ng/dL

6 days-2 months: 80-275 ng/dL

3-11 months: 86-265 ng/dL

1-5 years: 92-248 ng/dL

6-10 years: 93-231 ng/dL

11-19 years: 91-218 ng/dL

 

Adult (≥20 years): 80-200 ng/dL

 

For SI unit Reference Values, see www.mayocliniclabs.com/order-tests/si-unit-conversion.html

Day(s) Performed

Monday through Saturday

CPT Code Information

84480

LOINC Code Information

Test ID Test Order Name Order LOINC Value
T3 T3 (Triiodothyronine), Total, S 83124-8

 

Result ID Test Result Name Result LOINC Value
T3 T3 (Triiodothyronine), Total, S 83124-8

Test Classification

This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

Report Available

1 to 3 days