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For hours, walk-ins and appointments.Free thyroxine index; T3 uptake (THBR); thyroid-stimulating hormone (TSH); thyroxine (T4)
This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7 or B8, vitamin H, or coenzyme R). It is recommended to ask all patients who may be indicated for this test about biotin supplementation. Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.
Within 1 day
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
For more information, please view the literature below.
Thyroid Cascade Testing: Differential Laboratory Diagnosis of Thyroid Function
Serum (preferred) or plasma
2 mL
0.7 mL (Note: This volume does not allow for repeat testing.)
Red-top tube, gel-barrier tube, or green-top (lithium heparin) tube. Do not use oxalate, EDTA, or citrate plasma.
If a red-top tube or plasma is used, transfer separated serum or plasma to a plastic transport tube.
Room temperature
Temperature | Period |
---|---|
Room temperature | 14 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Plasma specimen
See individual tests.
Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
---|---|---|---|---|---|---|
000620 | Thyroid Panel With TSH | 90224-7 | 004264 | TSH | uIU/mL | 11580-8 |
000620 | Thyroid Panel With TSH | 90224-7 | 001149 | Thyroxine (T4) | ug/dL | 3026-2 |
000620 | Thyroid Panel With TSH | 90224-7 | 001156 | T3 Uptake | % | 3050-2 |
000620 | Thyroid Panel With TSH | 90224-7 | 001164 | Free Thyroxine Index | 32215-6 |
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