The measurement of antibodies against thyrotropin receptors is used to investigate various autoimmune diseases of the thyroid, such as:
- Differential diagnosis of etiology of thyrotoxicosis in patients with ambiguous clinical signs or when contraindicated (eg pregnancy or lactation) thyroid testing with radioisotopes
- In the diagnosis of Graves' disease
- Determining the risk of neonatal thyrotoxicosis in the newborn of a woman with active or past Graves' disease
- Differential diagnosis of thyrotoxicosis in pregnancy and manifestation or recurrence of Graves' disease in the first trimester
- Assessing the risk of recurrent Graves' disease after treatment
Antibodies against thyroid hormone (TSH) receptors, also called "thyroid-stimulating immunoglobulin", are autoantibodies that may be stimulatory, blocking, or binding.
TSH receptor stimulating antibodies stimulate the production of cyclic adenosine monophosphate, which in turn triggers the release of thyroxine (T4) and triiodothyronine (T3), resulting in symptoms of hyperthyroidism.
TSH receptor blocking antibodies prevent the thyroid hormone from binding to its receptor, resulting in symptoms of hypothyroidism.
Binding antibodies against TSH receptors bind to or near the TSH receptor on thyroid cells, thereby interfering with the action of TSH at its receptor site. Thus, thyroid hormone receptor antibodies may be present in various types of autoimmune thyroid diseases. The predominant type of antibody helps to differentiate the type of disease that exists.
Measurement of TSH receptor antibodies is mainly used to differentiate Graves' disease from non-autoimmune hyperthyroid disorders.
Neonates born from mothers with high levels of TSH receptor antibodies are at risk for thyrotoxicity due to cross-placental passage of immunoglobulins.
What Do Pathological Values Mean?
- Increase: Autoimmune thyroiditis, Graves' disease, hyperthyroidism, malignant exophtalmos
Important Note
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.