Nursing Study Guide/Toxic Goiter

Toxic Goiter is also known as Graves' Disease.

Definition

Graves' disease is an autoimmune disease characterized by a metabolic imbalance resulting from overproduction of thyroid hormones (thyrotoxicosis)".

1. Robert Graves, a doctor in the 19th century, discovered the condition, thus the name.
2. "In Graves' disease, the thyroid gland in the neck is diffusely enlarged and hyperactive, producing excessive thyroid hormones."
3. "Graves' disease can have an effect on many parts of the body such as the nervous system, eyes, skin, hair/nails, lungs, digestive system, muscles/bones and reproductive system."
4. Graves' disease is the most common form of hyperthyroidism.
5. Graves’ disease is “an autoimmune condition in which autoantibodies are directed against the thyroid-stimulating hormone (TSH) receptor. As a result, the thyroid gland is inappropriately stimulated with ensuing gland enlargement and increase of thyroid hormone production.
6. Graves' Disease is "characterized by the formation of autoantibodies that bind to receptors in thyroid cell membranes and stimulate the gland to hyperfunction."

How common is Graves' Disease, and who is at risk?

1. The onset of Graves Disease often follows stress or an infection.
2. Graves' Disease occurs eight times more frequently in women than in men, and most commonly between the ages of 20 and 40.
3. Graves' Disease tends to run in families.
4. “Risk factors for Graves disease include family history of hyperthyroidism or various other autoimmune disorders, high iodine intake, stress, use of sex steroids, and smoking."

Signs and symptoms

1. Classic characteristics of Graves Disease include triad of goiter, exophthalmos, and pretibial myxedema.

“ Goiter means enlargement of thyroid gland, exophthalmos is “swelling of the tissue behind the eyeballs causing protrusion of the eyeball" and pretibial myxedema is “lumpy, reddish-colored thickening of the skin, usually on the shins". ”

1. Hyperthyroidism can be caused by Graves' disease, and the general signs and symptoms of Graves Disease are the same as those of hyperthyroidism.
2. In addition to the classic Graves' Disease triad of goiter, exophthalmos, and pretibial myxedema, other signs and symptoms of Graves Disease include:

• nervousness
• tremors
• palpitations
• shortness of breath
• weakness
• fatigue
• muscle wasting
• heat intolerance
• sweating

• double vision
• increased eye tearing
• diarrhea
• infrequent or absent menstrual periods
• abnormal breast enlargement in men
• weight loss
• increased hair loss
• brittle nails
• diminished sex drive

Stages and grades

1. Hyperthyroid phase
2. Spontaneous remission

Treatment

Labwork/Testing/Diagnosis

How is Graves Disease diagnosed?

1. "In the examination, the doctor will look for a goiter (enlarged thyroid gland), a rapid pulse, tremor, and any other evidence of Graves' disease. Blood tests will be performed to assess thyroid function."
2. A sample of blood can be checked for the presence of antithyroid antibodies. "More specific antibodies can be measured, but such a test is rarely needed."
3. Radioactive-iodine uptake test and thyroid scan, to discern whether the entire thyroid gland is overactive, or just part of it is overactive."

Treating Graves Disease

The choice of treatment depends upon the age and overall condition of the patient, the size of thyroid gland, and patient preference."

1. Treatment is not always needed: "Graves' disease may go into spontaneous remission, and therapy is required only during the hyperthyroid phase."
2. Treatments available: "Currently, there are at least three methods of treatment: drugs that inhibit production of thyroid hormone or provide symptomatic relief, the use of radioactive iodine to destroy part of the thyroid gland and thereby reduce hormone production, or surgical removal of part of the gland."

Radioactive iodine therapy

This is an alternative if drug treatment fails. You are given a capsule or a drink of water containing radioactive iodine. After being swallowed, the "radioiodine" is rapidly absorbed by the overactive thyroid cells and are destroyed by the radiation, so less thyroid hormone is produced.

The radioactivity disappears from the body within days. You should not undergo radioactive iodine therapy if you are pregnant as the radiation can adversely affect a developing fetus.

Surgery

Thyroidectomy is surgical removal of all or part of the thyroid gland. If only a single lump or nodule within the thyroid is producing too much hormone, the surgeon can take out just that small part of the gland. If the entire gland is overactive, which is more often the case, a total thyroidectomy is needed.

Surgery is the preferred treatment for people with a large goiter who chronically relapse after drug therapy, if there is a risk of cancer, and for people who refuse or are not candidates for radioactive iodine therapy, such as pregnant women. Depending on how much of the gland is left after surgery, you may need subsequent thyroid replacement therapy.

Medications

"The goals of medical therapy are blockade of peripheral effects, inhibition of hormone synthesis, blockade of hormone release, and prevention of peripheral conversion of T4 to T3. Restoration of a clinical euthyroid state may take up to 8 weeks. [Euthyroid: The state of having normal thyroid gland function.]

1. Blocking agents such as beta-blockers reduce sympathetic hyperactivity and decrease peripheral conversion of T4 to T3.
2. Guanethidine and reserpine have been used to provide sympathetic blockade and may be effective agents if beta-blockers are contraindicated or not tolerated.
3. Iodides and lithium work to block release of preformed thyroid hormone.
4. Thionamides prevent synthesis of new thyroid hormone."
5. "Additional treatment may be needed for the eye and skin symptoms."
6. "Eye symptoms may be helped by elevating the head of the bed, by applying eye drops, by sleeping with the eyelids taped shut, and, occasionally, by taking diuretics (drugs that hasten fluid excretion)."(7)
7. "Double vision may be helped by using eyeglass prisms."
8. Corticosteroids taken by mouth, x-ray treatment to the orbits, or eye surgery may be needed if the eyes are severely affected."
9. "[Topical application of] corticosteroid creams or ointments can help relieve the itching and hardness of the abnormal skin.
10. "Often the [eye and skin symptoms] disappear without treatment months or years later."

See also

• Thyroid Exam

Further reading

• "Graves' Disease". Mayo Clinic.
• "Frequently Asked Questions About Graves Disease". National Graves' Disease Foundation.
• "Understanding Graves' Disease -- the Basics". WebMD.
• Melissa Breedlove. "Introduction to Graves' Disease". Davidson College. (created for an undergraduate assignment)