Specimen Requirements


Thyroid-Stimulating Immunoglobulin (TSI)

Specimen Requirement

Collect SST/3 mL, after 30 minutes of clotting, promptly centrifuge and send.

Alternate sample: Red top, lavender EDTA or green top heparin. If collecting alternate, sample must be centrifuged within 2 hours, transfer 3 mL serum/plasma to a screw top transport tube, indicate sample type on tube and send.


The IMMULITE 2000 TSI assay designed for the specific Semi- Quantitative detection of stimulating autoantibodies using a bridging format and human TSH receptor fragment chimeric recombinant proteins.


Room temp: 14 days, Refrigerated: 14 days, Frozen: 14 days

Reference Range

By Report*


2-4 days

Clinical Use

The measurement of thyroid stimulating autoantibodies, in conjunction with other clinical and laboratory findings, is used as an aid in the diagnosis of patients suspected of having Graves’ disease.

Test Code