Graves disease

Other Names: Basedow disease; Exophthalmic goiter; Parry disease; Graves' hyperthyroidism Graves' disease is an autoimmune disorder that causes hyperthyroidism, or overactive thyroid. With this disease, your immune system attacks the thyroid and causes it to make more thyroid hormone than your body needs.

The thyroid is a small, butterfly-shaped gland in the front of your neck. Thyroid hormones control how your body uses energy, so they affect nearly every organ in your body—even the way your heart beats.

If left untreated, hyperthyroidism can cause serious problems with the heart, bones, muscles, menstrual cycle, and fertility. During pregnancy, untreated hyperthyroidism can lead to health problems for the mother and baby. Graves’ disease also can affect your eyes and skin.

Graves disease symptoms

Epidemiology

Graves’ disease is the most common cause of hyperthyroidism in the United States. The disease affects about 1 in 200 people.1

Riskfactors

Graves’ disease usually affects people between ages 30 and 50, but can occur at any age. 2 The disease is seven to eight times more common in women than men. 3 A person’s chance of developing Graves’ disease increases if other family members have the disease.

People with other autoimmune disorders are more likely to develop Graves’ disease than people without these disorders. Conditions linked with Graves’ disease include

• rheumatoid arthritis , a disorder that affects the joints and sometimes other body systems
• pernicious anemia , a condition caused by a vitamin B12 deficiency
• lupus, a chronic, or long-term, disorder that can affect many parts of your body
• Addison’s disease, a hormonal disorder
• celiac disease, a digestive disorder
• vitiligo , a disorder in which some parts of the skin are not pigmented
• type 1 diabetes

Cause

Graves disease is thought to result from a combination of genetic and environmental factors. Some of these factors have been identified, but many remain unknown.

Graves disease is classified as an autoimmune disorder, one of a large group of conditions that occur when the immune system attacks the body's own tissues and organs. In people with Graves disease, the immune system creates a protein (antibody) called thyroid-stimulating immunoglobulin (TSI). TSI signals the thyroid to increase its production of hormones abnormally. The resulting overactivity of the thyroid causes many of the signs and symptoms of Graves disease. Studies suggest that immune system abnormalities also underlie Graves ophthalmopathy and pretibial myxedema.

People with Graves disease have an increased risk of developing other autoimmune disorders, including rheumatoid arthritis, pernicious anemia, systemic lupus erythematosus, Addison disease, celiac disease, type 1 diabetes, and vitiligo.

Variations in many genes have been studied as possible risk factors for Graves disease. Some of these genes are part of a family called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders (such as viruses and bacteria). Other genes that have been associated with Graves disease help regulate the immune system or are involved in normal thyroid function. Most of the genetic variations that have been discovered are thought to have a small impact on a person's overall risk of developing this condition.

Other, nongenetic factors are also believed to play a role in Graves disease. These factors may trigger the condition in people who are at risk, although the mechanism is unclear. Potential triggers include changes in sex hormones (particularly in women), viral or bacterial infections, certain medications, and having too much or too little iodine (a substance critical for thyroid hormone production). Smoking increases the risk of eye problems and is associated with more severe eye abnormalities in people with Graves disease.

Inheritance

The inheritance pattern of Graves disease is unclear because many genetic and environmental factors appear to be involved. However, the condition can cluster in families, and having a close relative with Graves disease or another autoimmune disorder likely increases a person's risk of developing the condition.

Signs and symptoms

You may have common symptoms of hyperthyroidism such as

• fast and irregular heartbeat
• frequent bowel movements or diarrhea
• goiter
• heat intolerance
• nervousness or irritability
• tiredness or muscle weakness
• trembling hands
• trouble sleeping
• weight loss

Rarely, people with Graves’ disease develop a reddish thickening of the skin on the shins, a condition called pretibial myxedema or Graves’ dermopathy. This skin problem is usually painless and mild, but it can be painful for some.

GO can cause retracted eyelids, meaning the eyelids are pulled back from the eye. GO can also cause bulging eyes, double vision, and swelling around the eyes.

Diagnosis

Your health care provider may suspect Graves’ disease based on your symptoms and findings during a physical exam. One or more blood tests can confirm that you have hyperthyroidism and may point to Graves’ disease as the cause.

Other clues that hyperthyroidism is caused by Graves’ disease are

• an enlarged thyroid
• signs of Graves’ eye disease, present in about one out of three people with Graves’ disease.
• a history of other family members with thyroid or autoimmune problems

If the diagnosis is uncertain, your doctor may order further blood or imaging tests to confirm Graves’ disease as the cause.

A blood test can detect TSI. However, in mild cases of Graves’ disease, TSI may not show up in your blood. The next step may be one of two imaging tests that use small, safe doses of radioactive iodine. Your thyroid collects iodine from your bloodstream and uses it to make thyroid hormones; it will collect radioactive iodine in the same way.

Radioactive iodine uptake test. This test measures the amount of iodine the thyroid collects from the bloodstream. If your thyroid collects large amounts of iodine, you may have Graves’ disease.

Thyroid scan. This scan shows how and where iodine is distributed in the thyroid. With Graves’ disease, the entire thyroid is involved, so the iodine shows up throughout the gland. With other causes of hyperthyroidism such as nodules—small lumps in the gland—the iodine shows up in a different pattern.

Treatment

You have three treatment options: medicine, radioiodine therapy, and thyroid surgery. Radioiodine therapy is the most common treatment for Graves’ disease in the United States,4 but doctors are beginning to use medicine more often than in the past.5,6 Based on factors such as your age, whether you are pregnant, or whether you have other medical conditions, your doctor may recommend a specific treatment and can help you decide which one is right for you.

Radioiodine therapy For radioiodine therapy, you take radioactive iodine-131 (I-131) by mouth as a capsule or liquid. I-131, at a higher dose than the dose used for imaging tests, slowly destroys the cells of the thyroid gland that produce thyroid hormone. The dose of I-131 usually used for radioiodine therapy does not affect other body tissues. Although it’s unlikely, you may need more than one radioiodine treatment to bring your thyroid hormone levels into the normal range. In the meantime, treatment with medicines called beta blockers can control your symptoms.

Almost everyone who has radioactive iodine treatment later develops hypothyroidism, or underactive thyroid, because the thyroid hormone-producing cells have been destroyed. However, hypothyroidism is easier to treat and causes fewer long-term health problems than hyperthyroidism. People with hypothyroidism can completely control the condition with daily thyroid hormone medicine.

Doctors don’t use radioiodine therapy to treat pregnant women or women who are breastfeeding. Radioactive iodine can harm the fetus’ thyroid and can be passed from mother to child in breast milk.

Medicines Beta blockers. Beta blockers don’t stop your thyroid from producing thyroid hormone but can reduce symptoms until other treatments take effect. These medicines act quickly to relieve many of the symptoms of hyperthyroidism, such as trembling, rapid heartbeat, and nervousness. Most people feel better within hours of taking beta blockers.

Antithyroid medicines. Antithyroid therapy is the simplest way to treat hyperthyroidism. Antithyroid medicines cause your thyroid to make less thyroid hormone. These medicines usually don’t provide a permanent cure, but in some people, the effects last a long time after they stop taking the medicine. Doctors most often use the antithyroid medicine methimazole .

Doctors usually treat pregnant and breastfeeding women with antithyroid medicine, since this treatment may be safer for the baby than other treatments. Doctors use propylthiouracil more often than methimazole during the first 3 months of pregnancy because methimazole may harm the fetus, although this happens rarely. Also rarely, propylthiouracil may affect the fetus, but any effects are less harmful than having uncontrolled hyperthyroidism during pregnancy.

Once treatment with antithyroid medicine begins, your thyroid hormone levels may not move into the normal range for several weeks or months. The total average treatment time is about 12 to 18 months,7 but treatment can continue for many years in people who don’t want radioiodine or surgery to treat their Graves’ disease.

Antithyroid medicines can cause side effects in some people, including

• allergic reactions such as rashes and itching
• a decrease in the number of white blood cells in your body, which can lower resistance to infection
• liver failure, in rare cases
• Thyroid surgery

The least-used treatment for Graves’ disease is surgery to remove the thyroid gland. Sometimes doctors use surgery to treat people with large goiters, or pregnant women who are allergic to or have side effects from antithyroid medicines.

Before surgery, your doctor will prescribe antithyroid medicines to bring your thyroid hormone levels into the normal range. This treatment prevents a condition called thyroid storm—a sudden, severe worsening of symptoms—that can occur when people with hyperthyroidism have general anesthesia .

After surgery to remove your thyroid, you will develop hypothyroidism and need to take thyroid hormone medicine every day for life. After surgery, your doctor will continue to check your thyroid hormone levels and adjust your dose as needed.

Diet People with Graves’ disease may be sensitive to harmful side effects from iodine. Eating foods that have large amounts of iodine—such as kelp, dulse, or other kinds of seaweed—may cause or worsen hyperthyroidism. Taking iodine supplements can have the same effect.

Talk with your health care professional about what foods you should limit or avoid, and let him or her know if you take iodine supplements. Also, share information about any cough syrups or multivitamins that you take because they may contain iodine.

NIH genetic and rare disease info

• NIH info on Graves disease

Graves disease is a rare disease.

Graves disease Resources
Latest articles Most recent articles Ongoing trials	Wikipedia