Test Code T3UP T3 (Triiodothyronine), Uptake, Serum
Performing Laboratory
Northwell Health Laboratories
Methodology
Electrochemiluminescence Immunoassay (ECLIA)
Includes calculation of free thyroxine (T4) index when T4 is also ordered.
Reference Values
T3UP: 0.8-1.3 TBI Units
%T3UP: 28-41 %
FTI: 4.4-11.4 Index
%FTI: 1.4 - 4.8 %
Test Classification and CPT Coding
84479
Specimen Required
Container/Tube: Gold-top tube(s)
Specimen: 1 mL of serum
Transport Temperature: Refrigerate
Stability: 8 Days Room Temperature
14 Days Refrigerated
24 Months Frozen
Day(s) and Time(s) Performed
Monday through Sunday, Continuously
Computer Interface Code
PDM # 5300420