Test Code NFTI Free Thyroxine Index (FTI), Serum
Additional Codes
This test includes total T4 and T4 uptake
Specimen
Draw blood in plain red top tube or serum gel (gold) tube. 1.0 ml serum required.
Note: Label specimen with patient’s name (first and last), date of birth, date and time of draw, and phlebotomist’s initials.
Performing Location
NORDX
CPT Code
84436 Thyroxine, total
84479 T4 uptake
Collection Container
Plain red or serum gel (gold top)
Specimen Transport Temperature
Refrigerated
Day(s) Test Set Up
Monday through Friday
Volume
1.0 ml
Units of Measure
ug/dL
LOINC
3026-2
Methodology
Electrochemiluminescence Immunoassay (ECLIA)