Test Code TUPK T-Uptake, Plasma
Methodology
ElectrochemiluminescenceIncludes free thyroxine index (FTI).
Must order #T4 “T4 (Thyroxine), Total Only, Plasma,” in addition to #TUPK “T-Uptake, Plasma” for FTI calculation.
Performing Laboratory
St. Clair Hospital LaboratorySpecimen Requirements
1 plasma gel tube (1 mL of lithium heparin plasma). Centrifuge blood as soon as possible, or send unspun blood to laboratory within 4 hours of draw.Reference Values
0.80-1.30 µg/dLLow values may indicate hyperthyroidism. High values may indicate hypothyroidism.