Not recommended for routine thyroid screening.
Quantitative Electrochemiluminescent Immunoassay
Sun-Sat
Within 24 hours
Serum separator tube or plasma separator tube. Also acceptable: Lavender (EDTA), pink (K2EDTA), or green (sodium or lithium heparin).
Allow specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)
Refrigerated.
Grossly hemolyzed specimens.
After separation of cells: Ambient: 4 days; Refrigerated: 8 days; Frozen: 1 year
Test Number |
Components |
Reference Interval |
||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Free Thyroxine Index Calculation | FTI 1.7-4.2 | |||||||||||||||||
0070135 | T3 Uptake | 28-41% uptake | ||||||||||||||||
0070140 | Thyroxine |
|
Thyroxine, Free (FT4) (0070138) is the preferred test alternative for T3 uptake and Free Thyroxine Index tests.
FDA
FTI = Free Thyroxine Index
84479; 84436
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
0070135 | T3 Uptake | 3050-2 |
0070140 | Thyroxine | 3026-2 |
0070196 | Free Thyroxine Index Calculation | 32215-6 |
- Free Thyroxine Index
- FT4 Index
- FTI
- T3 uptake
- T7
- thyroxine
- Thyroxine Index