What Causes Graves’ Disease?
Graves’ disease is an autoimmune disease where the body’s immune system, for some reason, turns against a part or parts of the body. Although we know little about why this occurs, we do know that some patient’s families clearly can have apparent predispositions to Graves’ disease. As a result of this autoimmune event, patients with Graves’ disease produce proteins called thyroid stimulating immunoglobulins. These immunoglobulins have the ability to link to a type of keyhole on the thyroid cells thyroid stimulating hormone (TSH) receptor just as TSH will do. In this way, the thyroid stimulating immunoglobulins push the thyroid cells to produce hormone in a continuous and unregulated fashion. In fact, there is no way to turn it off since the thyroid stimulating immunoglobulin production is not controlled in any way. The thyroid cells basically get tricked into producing more and more thyroid hormone thus producing hyperthyroidism.
Graves’ Disease: What Does A Radioactive Iodine Scan Show?
If you possibly have Graves’ disease and your blood tests also demonstrate that your thyroid hormone level is too high (hyperthyroidism), this is when a radioiodine scan (thyroid scan) is indicated. In these cases, the thyroid stimulating hormone (TSH) will be very low and in cases of Grave’s disease, the thyroid stimulating immunoglobulin will be very high. The Graves’ disease patient may or may not have recognized symptoms of their hyperthyroidism.
During the thyroid scan, the patient will be given a small amount of radioactive iodine in a pill and a special imaging camera is utilized to determine how much iodine is taken up by the thyroid gland and if the thyroid takes up iodine throughout the thyroid gland or whether there is a single “hot” area in the thyroid, relative to the remainder of the thyroid gland (this is called a “hot nodule”). A high uptake of iodine by the thyroid gland is suggestive of Graves’ disease or hyperthyroidism. If a thyroid nodule has less iodine uptake than the rest of the thyroid gland, then the thyroid nodule is called a “cold nodule”. In patients with multinodular goiter, frequently several of the nodules of the thyroid will be cystic and filled with fluid. These cystic areas of a multinodular thyroid are expected to take up less iodine than the rest of the gland and appear “cold”.
Hot nodules are almost always non-cancerous but the preferred management of hot nodules is frequently surgery since it is a clear, safe and 100% effective therapy for the hyperthyroidism.
Graves’ Disease: When is a CT or MRI Scan ordered?
If you are having symptoms from your eyes, your doctor may order a CT or MRI of the orbit and skull base in order to determine the impact of the Graves’ disease upon the eye, eye muscles, orbital fat, and surrounding structures.
A comprehensive compilation of all physical examination and tests is utilized to make a diagnosis of Graves’ disease.
What Are The Treatments For Graves’ Disease?
There are Three Treatments for Graves’ Disease:
Antithyroid Medication
Your doctor will likely prescribe you a medication to control your hyperthyroidism. There are two medications which are commonly prescribed to control hyperthyroidism. The first is methimizole and the second is propthiouracil (PTU). These drugs prevent the thyroid from making thyroid hormone. These medications need to be prescribed by endocrinologists that understand how these medications work and potential side effects and complications from their use. These drugs usually take several weeks to work. These medications are generally not used long term for the management of Graves’ disease. They are much more commonly thought of as a “short term solution”. The hyperthyroidism will generally return following the stopping of either of these two medications.
There are several side effects that you should be aware of in antithyroid medications. You may develop allergic reactive to these medications. Additionally, nausea, vomiting, heart burn, metallic taste, loss of taste, and bone and muscle aches may occur. A rare condition of loss of your bloods white blood cells can occur as well and must be monitored for with these medications. This condition is called agranulocytosis. If you develop fever, cough, or cold symptoms while on these medications, contact your endocrinologist immediately. It can be very serious. These medications can be utilized to prepare you for Radioactive iodine therapy
Radioactive Iodine Therapy
Often your doctor may favor radioactive iodine therapy more than antithyroid medication because these drugs do not produce a long term solution to the Graves’ disease. The radioactive iodine is given to you in a capsule or pill type form. The radioactive iodine therapy may take months to actually produce the desired effect. Repeated treatments of radioactive iodine may be required to ultimately control Graves’ disease in up to 70% of patients. Radioactive iodine is generally not sought as a therapeutic option if the patient has eye or orbital changes as a result of their Graves’ disease.
Radioactive iodine is taken up by the thyroid cells that produce thyroid hormone. Because the Graves’ disease thyroid cells are being “tricked” to produce more and more thyroid hormone, the radioactive iodine is taken into the thyroid hormone producing thyroid cells and a radiation effect is produced.
How much radioactive iodine is recommended for the treatment of a patient with Graves’ disease is a current matter of debate.
In theory, the goal of radioactive iodine for Graves’ disease is to give enough iodine to effective treat the Graves’ disease and still maintain adequate thyroid hormone production by the remaining thyroid cells. However, in most circumstances, most Graves’ disease patients treated with radioactive iodine will eventually develop low thyroid hormone production (hypothyroidism) and therefore require thyroid hormone replacement long term.
If you are pregnant or plan on becoming pregnant within one year, radioactive iodine therapy should not be used.
Surgery
Surgery may be recommended for many reasons:
Surgery is 100% effective therapy for Graves’ disease
When the Graves’ thyroid gland is very large, thyroid surgery is generally considered the preferred treatment
When antithyroid medication and radioactive iodine may be ineffective
Some patients cannot take or tolerate antithyroid medication and radioactive iodine
Surgery requires a total thyroidectomy
Graves’ disease surgery should only be performed by highly expert thyroid surgeons. An occastional thyroid surgeon should not do this surgery.
If you have orbital disease, surgery is the preferred therapy for managing the Graves’ disease thyroid gland.
Requires life long thyroid hormone medications and monitoring following surgery.
References
https://www.thyroidcancer.com/graves-disease
