Test Code T3UP T3 (Triiodothyronine), Uptake
Additional Codes
EPIC: LAB2556
Methodology
Chemiluminescent Immunoassay
Used to determine total thyroxine (T4) binding capacity and used in
conjunction with total T4 to yield the free thyroxine index, an
indirect indicator of thyroid function.
Performing Laboratory
St. Joseph Hospital
Specimen Requirements
Preferred: Plasma
Draw blood in a light green-top (PST - lithium heparin gel) tube(s). (Hemolyzed specimen is not acceptable.) Spin down, separate plasma from cells within 2 hours of collection, and send 1 mL of lithium heparin plasma refrigerated.
Note: Label specimen as “plasma”.
Acceptable: Serum
Draw blood in a plain, red-top tube(s) or SST- serum gel tube(s). (Hemolyzed specimen is not acceptable.) Centrifuge, separate serum from cells within 2 hours of collection, and send 1 mL of serum refrigerated.
Note: Label specimen as “serum”
Reference Values
Males: 33-40%
Females: 30-39%
Day(s) Test Set Up
Monday through Sunday
Test Classification and CPT Coding
84479