Graves' disease is an autoimmune disease characterized by a metabolic imbalance resulting from overproduction of thyroid hormones (thyrotoxicosis).
It is named after Robert Graves, the 19th century Irish physician who first discovered the condition. In Graves' disease, the thyroid gland in the neck is diffusely enlarged and hyperactive, producing excessive thyroid hormones.
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.
Graves' disease is eight times more common in women than in men, occurs most frequently between the ages of 20 and 40 and often arises after an infection or physical or emotional stress.
It has a familial tendency. The disease is characterized by the formation of autoantibodies that bind to receptors in thyroid cell membranes and stimulate the gland to hyperfunction.
Generally, the symptoms of Graves' disease are identical to the symptoms of hyperthyroidism, a condition that can be caused by Graves' disease. Classic symptoms include an enlarged thyroid gland (goiter), nervousness, heat intolerance, weight loss, sweating, diarrhea, tremors, palpitations and exophthalmos (swelling of the tissue behind the eyeballs causing protrusion of the eyeball).
Graves' disease can also manifest with any or all of the following:
- Shortness of breath
- Pretibial myxedema (lumpy, reddish-colored thickening of the skin, usually on the shins)
- Double vision
- Muscle wasting
- Increased eye tearing
- Infrequent or absent menstrual periods
- Abnormal breast enlargement (men)
- Increased hair loss
- Diminished sex drive
- Brittle nails
Thyroid storm, a complication of Graves' disease, may lead to life-threatening heart, liver, or kidney failure. Thyroid storm begins suddenly and may be caused by a stressful event.
The signs and symptoms of thyroid storm include extreme irritability, high blood pressure, rapid heart rate, vomiting, high fever, delirium and coma. Left untreated, it can be fatal.
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.
Your physician may also order a radioactive-iodine uptake test and thyroid scan. These tests can help determine if the entire thyroid gland is overactive, or whether just a portion of the gland is overactive.
The choice of treatment depends upon the age and overall condition of the patient, the size of thyroid gland, and patient preference.
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.
Your doctor will prescribe either methimazole (Tapazole) or propylthiouracil (PTU) pills. These drugs act to prevent the thyroid from manufacturing the thyroid hormone.
The side effects of this medication may be drowsiness and minor lethargy; in rare cases, they can cause agranulocytosis, a blood disease. Most of the time, however, this form of therapy is safe and restores normal hormone balance within a couple of months.
Another medication, propranolol, is a beta-blocker that helps relieve the symptoms of Graves' disease including rapid heart rate, tremor, sweating and anxiety. Iodinated contrast agents can also provide effective treatment for hyperthyroidism of any cause.
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.
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.