Thyroid-Stimulating Immunoglobulin (TSI)
Hormone markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Thyroid-Stimulating Immunoglobulin (TSI) values sit together on one chart and you walk into your next appointment prepared.
What is Thyroid-Stimulating Immunoglobulin (TSI)?
A type of antibody that specifically stimulates the thyroid, driving it to make more hormone.
Thyroid-stimulating immunoglobulin is an antibody that acts like thyroid-stimulating hormone and pushes the thyroid to make extra hormone. Higher levels can be associated with Graves disease and its overactive thyroid, and the test may also help evaluate thyroid eye disease or thyroid activity in pregnancy. TSI measures the stimulating action specifically, so it is related to but not the same as the broader TSH receptor antibody test.
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References
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