Reviewed By: Pramod Kerkar, MD, FFARCSI

TSH is the acronym for Thyroid Stimulating Hormone and it is a type of pituitary hormone responsible to stimulate the thyroid gland for the production of thyroxine i.e. T4 and triidothyronine i.e T3, both of which further stimulate the metabolism of each tissue present in the human body. Even it acts as a glycoprotein hormone secreted and synthesized via thyrotrope cells present in ones’ anterior pituitary gland to regulate the thyroid’s endocrine function.

Overview of TSI Test

TSI test involves a blood test to measure the respective TSI antibody. The thyroid is a butterfly shaped small gland that remains present nearby one’s throat. Thyroid is responsible to make hormones to regulate the way, in which the body utilizes energy. It even has a significant role to regulate an individual’s body weight, muscular strength, body temperature and mood. TSI formation takes place in the pituitary gland of a patient. Too low or too high TSI levels indicate improper functioning of one’s thyroid.

Purpose of TSI Test

Endocrinologist or any other similar medical professional order to conduct TSI test in case a patient shows signs and symptoms of excessive thyroid hormone formation i.e. hyperthyroidism. In addition, TSI test is recommendable in case doctors suspect for Graves’ disease i.e. a common cause of the problem of hyperthyroidism. The test thus clarifies the exact cause of patients’ symptoms whenever there are abnormal levels of T3, T4 and TSH.

Is TSI High in Graves’ Disease?

Yes, TSI levels are high in Grave’s disease. In normal conditions, the thyroid gland takes up iodine to create thyroid hormones. Thus, measurement of the exact amount of radioactive iodine or technetium captured by one’s thyroid gland is useful to measure or detect its functions. Radiation dose associated with TSH tests is of small and does not involve any side effect. Radioactive thyroid scan and uptake tests are important to know the appropriate treatment to use in patients dealing with hyperthyroidism and Graves’ disease.

In case of Graves’ disease, immune system of a person creates antibodies causing growth of the thyroid and creation of thyroid hormones in excessive amounts than exactly required by the human body. Experts call these antibodies as thyroid stimulating immunoglobulins i.e. TSIs, which are able to bind various thyroid cell receptors known as docking stations for TSHs (hormones responsible to indicate thyroid for the production of hormones). Later on, TSI tricks the thyroid into growth and production of thyroid hormones in excessive amounts resulting in the problem of hyperthyroidism.

Graves’ disease is a common cause of hyperthyroidism i.e. an autoimmune procedure, where immune cells of any patient create antibodies in opposition to TSH receptors on the cells of thyroid gland. These autoantibodies are responsible for stimulating the growth of thyroid leading to goiter or diffuse enlargement and production of thyroid hormones in excessive amounts leading to hyperthyroidism.

Graves’ disease combined with the problem of hyperthyroidism characterizes the presence of thyroid enlargement in diffused form, suppression of pituitary gland i.e. TSH, T3 and T4 elevations, TSH receptor antibodies in human body and uptake of elevated radioactive iodine by one’s thyroid gland. In addition, the problem has a few clinical symptoms, like increase in perspiration, weight loss, tremor, anxiety, frequent bowel movements and rapid pulse and heart rate.

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Pramod Kerkar

Written, Edited or Reviewed By:


Pain Assist Inc.

Last Modified On: May 17, 2018

This article does not provide medical advice. See disclaimer

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