Test Directory

Total T4

Loinc

Expected Turnaround

24 hours

Information

The determination of T4 can be utilized for the following indications: the detection of hyperthyroidism, the detection of primary and secondary hypothyroidism, and the monitoring of TSH‑suppression therapy.

Collection Information

Methodology

Electrochemiluminescence-immunoassay (ECLIA)

Limitations

Autoantibodies to thyroid hormones can interfere with the assay.

Rejection Criteria

Specimen Stability

Room temperature: 4 days Refrigerated: 8 days Frozen: 24 months

Alias

Total T4; T4, Serum; T4 (Thyroxine), Total; Thyroxine (T4); Thyroxine, Total

Container Type

Serum, gel separator, SST

Minimum Volume

1 ML

Age Range

0 - 999

Sex

Generic

Units of Measure

μg/dL

Reference Range

4.5 μg/dL - 11.7 μg/dL

Panic Range