Key words: hyperthyroidsim, thyrotoxicosis, Graves’ disease, toxic goiter, thyroidectomy Abstract Hyperthyroidism is defined as the excessive function of the thyroid gland. This is a very common disorder that is said to be present in 1. 5 to 2. 0% of women in the United States. Patients with this condition has clinical manifestations that include hyperactivity, irritability, nervousness, muscle weakness, weight loss increased appetite, heat intolerance and sweating, diarrhea, warm moist skin, fine tremor of the hand, and variable enlargement of the thyroid gland The most common etiology is Graves’ disease or diffuse toxic goiter.
It has a peak incidence between the ages of 20 and 40, with women being affected up to seven times more commonly than men. The three primary methods in the management of hyperthyroidism include the use of antithyroid drug therapy, surgical removal of the thyroid gland and the destruction of the thyroid tissue with radioactive iodine. The purpose of this paper is to provide information regarding hyperthyroidism and to discuss some aspects about its management. Hyperthyroidism: Bigger May Not Always Be Better Hyperthyroidism is defined as the excessive function of the thyroid gland (Braunwald, et al, 2001).
It is commonly used interchangeably with the medical condition known as thyrotoxicosis which is the hypermetabolic state brought about by elevated levels of thyroid hormones (Cotran, et al, 1999). However, both terms are not synonymous to each other. When the hormone excess is secondary to the hyperfunction of the thyroid gland, such as in the case of Graves’ disease, the thyrotoxicosis may be correctly called hyperthyroidism. However, since other conditions can lead to elevated hormone levels other than a hyperactive thyroid gland, any increase in thyroid hormone is properly referred to as thyrotoxicosis (Cotran, et al, 1999).
Whatever the case may be, both conditions have similar clinical manifestations. These include hyperactivity, irritability, nervousness, muscle weakness, weight loss increased appetite, heat intolerance and sweating, diarrhea, warm moist skin, fine tremor of the hand, and variable enlargement of the thyroid gland (Braunwald, et al, 2001). Causes of hyperthyoidism There are several disorders associated with hyperthyroidism. The most common etiology is Graves’ disease or diffuse toxic goiter which accounts for 60 to 80% of thyrotoxicosis in general.
It has a peak incidence between the ages of 20 and 40, with women being affected up to seven times more commonly than men (Braunwald, et al, 2001). This is a very common disorder that is said to be present in 1. 5 to 2. 0% of women in the United States (Cotran, et al, 1999). Other causes of hyperthyroidism include toxic multinodular goiter, toxic adenoma, functioning thyroid carcinoma metastases, excessive intake of iodine and secondary disorders outside the thyroid such as certain pituitary gland tumors, tumors that secrete chorionic gonadotropin hormone and gestational thyrotoxicosis in pregnancy (Braunwald, et al, 2001).
Management of hyperthyroidism The three primary methods in the management of hyperthyroidism include the use of antithyroid drug therapy, surgical removal of the thyroid gland and the destruction of the thyroid tissue with radioactive iodine. Drug therapy is most useful in children with small glands and mild disease. This is the only therapy that leaves an intact thyroid gland, but it does require a long period of treatment (Katzung, 2001). Surgery is the treatment of choice in patients under age 35 with severe thyrotoxicosis and large goiters.
The main advantage of thyroidectomy is immediate cure of the disease (Schwartz, et al, 1999). In addition, about 80 to 90% of patients will require lifetime thyroid supplementation following surgery to avoid hypothyroidism (Katzung, 2001). Older patients in the United States undergo radioiodine treatment. It is the preferred treatment in patients without underlying heart diseases. However, it is contraindicated in pregnant or nursing women. The key objective in any of these treatments is controlling the increased level of the thyroid hormone released into the blood. Summary
Hyperthyroidism is a common disease affecting mostly women. Emphasis should be given to its cardiac manifestations which could lead to severe complications. The diagnosis of hyperthyroidism should cause concern to its underlying etiology which could be a primary tumor or a metastasis from a distant tumor. Several treatment options are available to thyroid patients. Careful selection of the treatment modality and good patient compliance to medication should lead to a favorable treatment outcome.
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