TSI (Thyroid Stimulating Immunoglobulin) : 1001555

Test Code
TSIGG or 1001555

Alias/See Also
Long Acting Thyroid Stimulator, (LATS),TSIG,Thyretain (TM), Thyroid Stimulating Antibody

CPT Codes

Serum separator tube.

Transport Container
Centrifuge the serum separator tube and transport 1 mL serum. (Min: 0.2)

Transport Temperature

Specimen Stability
After separation from cells: Ambient: Unacceptable; Refrigerated: 21 days; Frozen: 60 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis. Grossly lipemic Grossly icteric.

In Vitro Bioassay

Setup Schedule
Monday - Saturday

Report Available
2-3 days (From receipt at performing laboratory)

Reference Range
less than 140% Baseline

Clinical Significance
Graves' disease is a classic form of hyperthyroid disease, affecting approximately 0.4% of the population of the United States. It is caused by IgG immunoglobulins, collectively known as thyroid stimulating immunoglobulins (TSI). Patients who are candidates for antithyroid drug therapy may not respond to this treatment when TSI levels are markedly elevated. The determination of TSI can also assist in predicting hyperthyroidism in neonates, due to placental transmission of the immunoglobulins from a mother with hyperthyroidism.

Performing Laboratory
Quest Diagnostics

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.