PATCHS PROGRAM PUBLIC HEALTH NURSING ADVOCATES TEACHING CHILD HEALTH AND SAFETY HEALTH CARE PROGRAM FOR CHILDREN IN FOSTER CARE (HCPCFC)
Volume 1, Issue 16		APRIL 2004

Medical Information Fact Sheet

Thyroid Gland:

The thyroid gland is a butterfly shaped gland located at the base of the neck, just below the Adam’s apple. The thyroid gland weighs less than an ounce but has an enormous impact on a person’s health. Every aspect of metabolism from heart rate to how quickly calories are burned is regulated by thyroid hormones.

Cells in the thryoid gland secrete two hormones; thyroxine (T4) and Triiodothyronine (T3). These hormones maintain the rate, at which the body uses fats and carbohydrates, helps control body temperature, influences heart rate and regulates production of protein.

As long as the thyroid gland produces the right amount of the hormones then metabolism will function normally. However sometimes there may be too much or too little of these hormones produced. If too much is produced then the person is know to have hyperthyroidism. If too little is produced then the person is said to have hypothyroidism. The release of these hormones is dependent on an adequate supply of iodine which most Americans get in their diet daily by using iodized salt.

The thryoid gland also secretes Calcitonin which is released to regulate the calcium levels within the blood by controlling the activity within the bones.

Hyperthyroidism:

Hyperthyroidism is a condition that is caused by overproduction of thryoid hormones. This disease is more common in women and typically occurs in young or middle aged adults.

Causes:

Graves’ disease:
One cause of hyperthyroidism is Graves’ disease, an autoimmune disease in which antibodies produced by the immune system stimulate the thyroid to produce too much T4. These antibodies usually help protect the body against viruses, bacteria and other foreign substances that invade your body. In Graves’ disease these antibodies mistakenly attack your thyroid gland and occasionally the tissue behind the eyes and the skin of the lower legs. The exact cause of Graves’ disease is unknown but it may be genetically predisposed. A viral infection or stress can also trigger Graves’ disease.

Hyperfunctioning thyroid nodules:
Another cause of hyperthyroidism is adenomas that produce too much thyroxine. An adenoma is a part of the gland that has walled itself off from the rest of the gland, forming noncancerous (benign) lumps that may cause an enlargement of the gland. Not all adenomas produce thyroxine but many do and researchers are unsure of what causes them to begin producing the hormone.

Thyroiditis:
Sometimes the thyroid gland can become inflamed for unknown reasons. This inflammation can cause excess hormones to leak into the blood.

Signs and Symptoms:

Hyperthyroidism can mimic other disorders, which can make it difficult to diagnose.
Signs and symptoms include:

· Sudden weight loss, even when appetite and food intake remain normal or increase
· Rapid or irregular heartbeat
· Nervousness, irritability or tremors
· Sweating
· Changes in menstrual patterns
· Increased sensitivity to heat
· Changes in bowel patterns, especially more frequent bowel movements
· An enlarged thryoid (goiter), which may appear as swelling at base of the neck
· Fatigue, muscle weakness
· Difficulty sleeping
· Sometimes eye changes may occur commonly called Graves’ ophthalmopathy which is seen as the eyes protruding out of the socket and the eyes may become very dry.

Diagnosis:

Diagnosis is usually made by medical history, physical exam and lab tests. The diagnosis is confirmed with blood tests that show elevated levels of the thryoid hormones. Further test like radioactive iodine uptake tests or a thryoid scan can be done to further determine the cause of the overactive thryoid.

Treatment:

There are several treatments available for hyperthyroidism.

Radioactive iodine:
The most common treatment used. Taken by mouth, radioactive iodine is absorbed by the thryoid gland, where it causes the gland to shrink and symptoms to subside, usually within 2-3 months. Because this medication causes thyroid activity to slow considerably, the patient may need to take medication every day to replace the thyroxine.

Antithyroid Medications:
These medications gradually reduce symptoms of hyperthyroidism by preventing the thryoid from producing excess amounts of hormones. Symptoms usually improve within 6-8 weeks, but treatment with these medications continues for a year or more. For many people this clears up the problems while others may experience a relapse. This may include the medications Propylthiouracil and Methimazole.

Surgery:
If the drugs cannot be tolerated and radioactive iodine is not an option then surgery may be done. Typically surgery is reserved for severe cases where the enlarged thryoid gland is making breathing and swallowing difficult.

During the surgery the doctor may remove part or all of the thyroid gland depending on the problem and severity. Risk of the surgery may include damage to vocal cord and the parathyroid glands. The parathyroid gland controls the level of calcium in the blood. In addition the person will have to have lifelong treatment with Synthroid to supply the body with normal amounts of thryoid hormones.

Hypothyroidism:

Hypothyroidism is the condition that results from the thryoid gland not producing enough hormones. It affects mostly women over the age of 40. Hypothyroidism usually develops slowly, so only about half of the cases are diagnosed early.

Causes:

Hashimoto’s Thyroiditis:
An autoimmune disorder where the body’s own immune system attacks the thryoid gland. The thryoid becomes inflamed and the amount of hormones it produces is affected.

Medications:
Treatment with radioactive iodine or other medications can lead to decrease production of hormones in the thyroid gland. Antithyroid medications can do this. One medication in particularly can lead to hyperthyroidism and that is lithium.

Surgery:
Partial or total removal of the thryoid can lead to little or no production of thyroid hormones.

Radiation:
Radiation used to treat cancers in the head and neck can contribute to hypothyroidism.

Other:
Less often hypothyroidism may be a result of congenital disease, pituitary disorder, pregnancy and iodine deficiency.

Signs and Symptoms:

Signs and symptoms may vary depending on the severity of the hormone deficiency. Signs and symptoms may include:

· Increased sensitivity to cold
· Constipation
· Pale, dry skin
· A puffy face
· Hoarse voice
· Elevated blood cholesterol levels.
· Unexplained weight gain
· Heavier than normal menstrual periods
· Depression.

Diagnosis:

Diagnosis is usually made by medical history, physical exam and lab tests. The diagnosis is confirmed with blood tests that show decreased levels of the thryoid hormones.

Treatment:

Standard treatment for hypothyroidism includes daily use of a synthetic thryoid hormone levothyroxine (Levothroid, Synthroid). The medicat6ion restores adequate hormone levels, shifting the body back into normal gear. This medication treatment is usually lifelong. The doctor will spend some time adjusting the medication dosage by running standard lab tests and seeing if the current dosage is working. If the levels of hormones are not increasing the doctor will usually up the dosage. This is usually done after about 2-3 months.

Mayo Clinic. (2002, September 9). Hyperthyroidism. Retrieved on January 18, 2004 from the World Wide Web: http://www.mayoclinic.com/invoke.cfm?id=DS00344
Mayo Clinic. (2002, October 8). Hypothyroidism. Retrieved on January 18, 2004 from the World Wide Web: http://www.mayoclinic.com/invoke.cfm?id=DS00353

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HCPCFC PROGRAM UPDATES and ANNOUNCEMENTS!!! This newsletter will now be produced quarterly. It will be produced in the months of January, April, July and October.

 

Editor: Kristen Thompson, PHN
Contributors: William Chavez, PHN, MBA, Assistant Nurse Manager and Judy Earp, MHA, Director of Public Health Nursing.