Thyroid peroxidase test
A blood test done to detect autoantibodies directed against thyroid peroxidase (TPO), an enzyme in the thyroid gland that is very important to the production of thyroid hormones. TPO is found in thyroid follicle cells where it catalyzes the iodination of T4 and T3 in the biosynthesis of thyroid hormones.
Autoantibodies to thyroid peroxidase (abbreviated TPOAb) are produced by the body itself. TPOAb can attack the thyroid and damage thyroid function. These antibodies are present in a high proportion (70% to 90%) of people with chronic thyroiditis. These antibodies are also present in lesser numbers of people with other thyroid diseases. Other autoimmune disorders such as Sjogren syndrome, lupus, rheumatoid arthritis, and pernicious anemia are sometimes positive for TPOAb. Small numbers (around 3%) of people may have TPOAb show no evidence of disease. The chance of having TPOAb is greater in females and increases with age.
This test goes by a confusing number of names, including thyroid peroxidase (TPO) antibody (TPOAb) test, thyroid peroxidase autoantibody test, antimicrosomal antibody test and antithyroid microsomal antibody test.
- Thyroid scan
An image taken of a patient’s thyroid gland after the patient swallows radioactive iodine or technetium. The image shows the thyroid gland in action as it accumulates radioactive material. Thyroid scanning is used to determine how active thyroid tissue is in manufacturing thyroid hormone. This can help a physician determine whether inflammation of the thyroid […]
- Thyroid stimulating hormone
A hormone produced by the pituitary gland at the base of the brain in response to signals from the hypothalamus gland in the brain. Thyroid stimulating hormone (TSH) promotes the growth of the thyroid gland in the neck and stimulates it to produce more thyroid hormones. When there is an excessive amount of thyroid hormones, […]
- Thyroid stimulating immunoglobulin (TSI)
A form of immunoglobulin G (IgG) that can bind to thyrotropin (TSH) receptors on the thyroid gland. TSIs mimic the action of TSH, causing excess secretion of thyroxine and triiodothyronine. The TSI level is abnormally high in persons with hyperthyroidism due to Graves’ disease.
- Thyroid storm
Thyroid storm is a severe, life-threatening condition caused by an excess of thyroid hormone. A number of factors can be involved in causing thyroid storm, including over-replacement of thyroid hormones or discontinuing medications taken to treat hyperthyroidism. Symptoms of thyroid storm can include fever (potentially as high as 105-106 degrees F), racing pulse, nausea,vomiting, diarrhea, […]
Surgery to remove part or all of the thyroid gland. Thyroidectomy might be done to remove a tumor or to treat hyperthyroidism or goiter (enlarged thyroid gland). Complications of the surgery can include vocal cord paralysis and accidental removal of the parathyroid glands, which are located behind the thyroid gland. Because the parathyroid glands regulate […]