T Uptake
Also known as: T UPTAKE
Use
The T Uptake test is utilized to measure the uptake of thyroid hormones by thyroid-binding proteins in serum. While not recommended for routine screening of thyroid disorders, it helps in calculating the free thyroxine index, which can provide more insight into thyroid function when used alongside other tests like the Thyroid Stimulating Hormone (TSH) or Free T4. Due to its limited standalone clinical value, it is more of a supplementary test rather than a primary diagnostic tool.
Special Instructions
For initial screening of thyroid disorders, it is advised to use the Thyroid Stimulating Hormone (TSH) test instead. The preferred alternative to this test is Free T4. Samples should be separated from cells as soon as possible and stored appropriately to maintain stability. Please consult with the ordering guidelines for specific patient preparation instructions.
Limitations
The T Uptake test alone provides limited clinical value and is not suitable as a standalone diagnostic test for thyroid disorders. It functions as an adjunct in calculating the free thyroxine index and may not accurately reflect thyroid status when used independently. Node: Environment, physiological and medication-related variables can affect test outcomes.
FDA ApprovedNew York Approved
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 74795-6
Result Turnaround Time
0-1 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
Serum Separator Tube (SST). Also acceptable: Lavender (K2EDTA or K3EDTA), pink (K2EDTA), or green (lithium heparin)
Collection Instructions
Allow specimen to clot completely at room temperature. Separate from cells ASAP or within 2 hours of collection.
Causes for Rejection
Grossly hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 8 days |
| Refrigerated | 2 weeks |
| Frozen | 2 years |