Thyroid Gland Disorders: Hyperthyroidism

Description

Hyperthyroidism means an overactivity of the thyroid gland, resulting in too much thyroid hormone in the bloodstream. The oversecretion of thyroid hormones leads to overactivity of the body's metabolism. Hyperthyroidism exists in several different forms. These include:

• Graves' disease or diffuse toxic goiter (goiter refers to an enlarged thyroid which may cause a bulge in the neck). Graves' disease is most often associated with hyperthyroidism. Graves' disease is suspected to be caused by an antibody which overstimulates the thyroid, resulting in excess production of thyroid hormone. Graves' disease is categorised as an autoimmune disorder (a dysfunction of the body's immune system). The disease is most common in young to middle-aged women and tends to run in families.
• Toxic nodular goiter or multinodular goiter . Hyperthyroidism caused by toxic nodular goiter is where one or more nodules of the thyroid becomes overactive. The overactive nodules actually act as benign thyroid tumours. The cause of toxic nodular goiter is not known.
• Thyroiditis . Thyroiditis, an inflammation of the thyroid gland, causes temporary hyperthyroidism, usually followed by hypothyroidism . There are 3 types of thyroiditis: Hashimoto's thyroiditis , subacute granulomatous thyroiditis and silent lymphocytic thyroiditis.
• Also, if a person takes too many thyroid hormone tablets, hyperthyroidism may occur.

Symptoms and Signs

The most common symptoms ( see here for list) of hyperthyroidism may differ from one individual to another as well as depending on the type of hyperthyroidism.
For example the symptoms of Graves' disease are identical to hyperthyroidism, with the addition of 3 other symptoms: goiter , exophthalmos (bulging eyes) and thickened skin over the shin area.
Symptoms of toxic nodular goiter do not include exophthalmos or skin problems, as in Graves' disease.

Diagnosis and Treatment

In addition to a complete medical history and medical examination, diagnostic procedures for hyperthyroidism may include the measurement of thyroid hormone in the bloodstream and/or a thyroid scan, which uses a radioactive substance to create an image of the thyroid as it is functioning.
Treatment for hyperthyroidism is very specific for each patient. The goal of treatment is to restore the thyroid gland to normal function, producing normal levels of thyroid hormone.
Treatment options include the use of antithyroid drugs that help lower the level of thyroid hormones in the blood; radioactive iodine , in the form of a pill or liquid, which damages thyroid cells so that production of thyroid hormones is slowed down, surgery to remove part of the thyroid (the overactive nodule), use of beta blocking agents , which block the action of the thyroid hormone on the body (these drugs do not change the levels of thyroid hormone in the blood, but make the patient feel better).

The information in this page is presented in summarised form and has been taken from the following source(s):
1. University of Maryland Medical System Online Health Guides: http://www.umm.edu/