ARUP Test Catalog
ARUP Consult Guide
Lab Tests Online
Thyroid Stimulating Immunoglobin (TSI)

Mnemonic:    [TSI]
Name:    Thyroid Stimulating Immunoglobin (TSI)
Specimen:    1 mL serum from a Red SST or Red top tube. Plasma is unacceptable. FREEZE
Minimum Spec:    0.7 mL
Neonatal Spec:    0.7 mL serum
Transport Temp:    FREEZE
Spec Stability:    Stable 6 days refrigerated.
Ref Lab/Code:    ARUP 0099430
Reference Range:    < 130 % basal activity
  Method:    Bioassay/Chemiluminescence
Note:    Positive results (>/= 130% basal activity) are consistent with Grave's disease. For any results 130% and above the following statement will be added: "An elevated TSH value above 10 mIU/L may produce a low positive result."