Test Details
Methodology
Electrochemiluminescence immunoassay (ECLIA)
Result Turnaround Time
Within 1 day
Special Instructions
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.
Specimen Requirements
Test Includes
Thyroid-stimulating hormone (TSH); free thyroxine, direct
Specimen
Serum (preferred) or plasma
Volume
1 mL
Minimum Volume
0.7 mL (Note: This volume does not allow for repeat testing.)
Container
Red-top tube, gel-barrier tube, or green-top (lithium heparin) tube. Do not use oxalate, EDTA, or citrate plasma.
Storage Instructions
Room temperature
Causes for Rejection
Citrate plasma specimen; improper labeling
Collection Instructions
If a red-top tube or plasma is used, transfer separated serum or plasma to a plastic transport tube.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 7 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 224576 | TSH+Free T4 | 004264 | TSH | uIU/mL | 11580-8 | |
| 224576 | TSH+Free T4 | 019745 | T4,Free(Direct) | ng/dL | 3024-7 | |
| Order Code | 224576 | |||||
| Order Code Name | TSH+Free T4 | |||||
| Order Loinc | ||||||
| Result Code | 004264 | |||||
| Result Code Name | TSH | |||||
| UofM | uIU/mL | |||||
| Result LOINC | 11580-8 | |||||
| Order Code | 224576 | |||||
| Order Code Name | TSH+Free T4 | |||||
| Order Loinc | ||||||
| Result Code | 019745 | |||||
| Result Code Name | T4,Free(Direct) | |||||
| UofM | ng/dL | |||||
| Result LOINC | 3024-7 |