Goiter

Goiter is the abnormal swelling of the thyroid gland, often resulting in a swollen mass in the neck. The thyroid gland is located in front of the windpipe. It has a right and left lobe, both of which are connected by a narrow band of thyroid tissue. The gland is roughly butterfly-shaped and is responsible for the production and secretion of the hormones thyroxin and triiodothyronine. These hormones regulate growth and metabolism. Many processes, such as heart rate, blood pressure, growth, and breathing, depend upon the hormones released by the thyroid gland.

Goiter is often a sign of thyroid problems like hyperthyroidism or hypothyroidism. The thyroid gland is located in the neck, and it plays an important role in energy levels and the production of hormones in the body. Goiter is usually painless, but it may interfere with breathing or swallowing. In some cases, the entire gland may become enlarged or swollen, while in others, nodules, enlargement, or swellings may develop in only one or a few parts of the gland.

The most common cause of goiter is a deficiency of iodine in the diet. Iodine is a mineral needed by the thyroid gland to produce necessary hormones. This explains why iodized salt is common in developed countries.

Other important causes of goiter are the presence of nodules in the thyroid gland and problems in hormone production.

Goiters that become noticeably enlarged require treatment, as it interferes with breathing, swallowing, and certain activities like singing.

Goiter is treated by addressing the underlying causes.

Goiters are mostly painless, but a thyroid gland that is inflamed can be painful.

Goiters often do not cause any signs or symptoms, especially if they are small. When they do, it may include the following:

• Tightness in the throat
• Visible or palpable swelling at the base of the neck, often seen when shaving or applying makeup
• Coughing
• Hoarseness
• Difficulty swallowing or breathing due to the large goiter pressing on the windpipe or gullet

Other symptoms include:

• Nervousness
• Hyperactivity
• Fatigue
• Increased sweating
• Increased appetite
• Weight loss
• Hair loss

These symptoms may occur because of the underlying cause of goiter, rather than the goiter itself.

Due to hypothyroidism, symptoms that may occur include:

• Constipation
• Cold intolerance
• Personality changes
• Hair loss
• Weight gain
• Forgetfulness

Goiter is caused by a swollen or enlarged thyroid gland. The thyroid gland produces two main hormones called thyroxine (T4) and Triiodothyronine (T3).

These hormones regulate burning of fats and carbs for energy, control production of proteins, and regulate body temperature and heart rate. The thyroid produces another hormone called calcitonin, which controls the amount of calcium in the bloodstream. The production of these hormones by the thyroid gland is regulated in turn by the pituitary gland and the hypothalamus.

The pituitary gland and the hypothalamus release a hormone called thyroid-stimulating hormone (TSH), which, as the name implies, jumpstarts the thyroid to produce hormones. Production of TSH depends on the levels of T4 and T3 in the bloodstream. 

Iodine deficiency is the most common cause of goiter. The thyroid needs iodine to produce T4; when the pituitary gland and hypothalamus sense low levels of T4, they release more TSH. The additional TSH works only to increase the size of the thyroid gland, causing goiter.

Iodine deficiency is very common in places that do not use iodized salt. Low consumption of seafood causes iodine deficiency, especially in inland and high-altitude regions. Iodine deficiency can also be caused by consumption of foods that reduce production of thyroid hormones, such as cabbage, cauliflower, and broccoli. 

Besides an iodine deficiency, the thyroid gland may become enlarged and result in goiter due to the following factors:

• Graves’ disease is a condition in which the immune system attacks the thyroid gland in a way that causes it to produce excess T4, resulting in goiter. If untreated, it may cause weight loss, emotional liability, depression, and mental or physical fatigue. The disease is the most common cause of goiter. Experts believe that heredity, age, stress, and gender affect the risk of developing Grave’s disease. Typically, it is found in people younger than forty. If you have a family history of this disease, you may be at risk. Women are also at a greater risk than men. Other auto-immune diseases, such as rheumatoid arthritis, diabetes mellitus, and Crohn’s disease, may also increase risk.
• In developed countries, the main cause of goiter is autoimmune disease. Women over the age of forty and people with a family history of the condition are at a greater risk. Hashimoto’s disease is also the result of problems in the immune system, this time causing the thyroid gland to produce too few hormones. Due to low thyroid activity, the pituitary gland and hypothalamus produce more TSH, resulting in goiter.
• Hyperthyroidism is also a cause of goiter. Other causes include excess iodine, thyroiditis (inflammation of the thyroid), benign thyroid tumors, and large amounts of tetraiodothyronine through dietary supplements or medication.
• Nodules in the thyroid, which can either be one (solitary) or multinodular (several), can cause goiter. Nodules are either solid or filled with fluid that develops in the sides of the thyroid gland, causing an increase in size. Causes include non-cancerous cysts; an adenoma, which is a solid, non-cancerous tumor; a cancerous tumor; and other rare causes. Thyroid nodules are mostly non-cancerous and do not progress to cancer.
• Inflammation can cause the thyroid gland to swell and result in goiter. Radiotherapy treatment, particularly to the neck, can also cause the thyroid gland to become inflamed. Different types of thyroiditis can be caused by infections from germs, such as bacteria and viruses.
• Thyroid cancer may cause goiter, but it is uncommon compared to nodules. Thyroid cancer tends to cause goiter on one side of the gland. Women with a family history of thyroid cancer, breast cancer, or radiation exposure can be at a greater risk for thyroid cancer. Age is also a factor. The types of thyroid cancers include:
  • Papillary thyroid cancer: This is a well-differentiated form of thyroid cancer, as well as the most common. It mostly develops in women of child-bearing age. It is less dangerous and spreads slowly, and thus is treatable.
  • Medullary thyroid cancer: This is also a well-differentiated form of thyroid cancer. Some may be associated with a genetic component. If it occurs without a genetic component, it is referred to as “sporadic”. It arises in non-thyroid cells located in thyroid gland.
  • Follicular thyroid cancer: This cancer spreads and recurs. Hurthle cell cancer is one such type.
  • Anaplastic thyroid cancer: This cancer is rare, but difficult to treat and is one of the most aggressive forms.
  • Thyroid lymphoma: This rare cancer begins in immune cells, which are located within the thyroid gland.
• Some people inherit a predisposition for thyroid swelling. Pregnancy may cause the thyroid gland to enlarge slightly.
• Smoking is also a cause of goiter. Thiocyanate in tobacco smoke may interfere with iodine absorption. 

To check whether your body is producing too much or too little thyroxin, or T3, the doctor will perform some blood tests. These tests will also help find the cause of goiter.

In hyperthyroidism, TSH levels are low or non-existent, while T4 levels are high. In hypothyroidism, TSH levels are high and T4 levels are low. The swelling of the thyroid gland confirms the diagnosis of goiter. The doctor will order additional tests to determine the cause of thyroid swelling, including:

• Radioactive scan: An injection of radioactive iodine is given. This provides a detailed picture of the gland.
• Ultrasound scan: This is a safe, painless test that creates images of organs and structures inside the body using sound waves. This method can determine if a nodule, cyst, or solid lump is present.
• Biopsy: This test may be performed if cancer is suspected. A biopsy is performed by inserting a thin needle into a nodule. A small tissue piece is taken from the nodule and examined under a microscope. The specialist will do the biopsy along with the ultrasound scan in order to see where the needle is being inserted.
• Other special blood tests, CT scans, or MRIs may be needed to establish the cause.

Questions may come up soon after receiving the diagnosis, so feel free to ask your doctor. Here are some good questions:

• What could be the causes of my condition?
• Is my goiter serious?
• What are the available treatments for my case? What are my choices if I have other health problems?
• What will happen if I choose not to have treatment?
• What are the solutions to improve the appearance of goiter?
• What are the medications I will take? How long will I take them?

Goiter usually has a cause that must be addressed to treat the condition. Depending on your appearance and health problems, your doctor might recommend the following:

• Watchful waiting may be necessary for small goiters, especially if tests show there is nothing wrong with the thyroid hormones.
• Medications that supply thyroid hormones like levothyroxine (Levothroid, Synthroid) may be provided for goiter with hypothyroidism. This will resolve symptoms of hypothyroidism and reduce the release of TSH, which often results in a reduction in goiter size. Anti-inflammatory medicines like aspirin and corticosteroids may be prescribed for inflammation of the thyroid. For goiters caused by hyperthyroidism, medicines like propylthiouracil and methimazole (Tapazole) are prescribed to normalize thyroid hormones.
• Radioactive iodine is used for a hyperactive thyroid. It is orally administered and ends up in the thyroid. The radiation from the iodine kills thyroid cells, which can help control a hyperactive thyroid. It is often used to reduce the size of the goiter. Because radioactive iodine kills thyroid cells, you may need to take thyroid hormones, like levothyroxine, for life.
• Surgery for goiter involves the partial or entire removal of the thyroid gland. Surgery is a choice for particularly large goiters, large nodular goiters with hyperthyroidism, or thyroid cancer. If a large section of the thyroid or the whole gland is removed, you may have to take thyroid hormone medication (levothyroxine) for life.

Goiter may respond to lifestyle changes, such as increasing iodine intake by using iodized salt or eating more seaweed. Some items rich in iodine include shrimp, shellfish, and seaweed. Even fruits and dairy in coastal areas contain good amounts of iodine. You need around 150 micrograms of iodine per day, especially for pregnant and breastfeeding women, infants, and children.

If you have a hyperactive thyroid, you may need to reduce iodine intake; simply reduce consumption of iodine-rich foods. Hyperthyroidism can be prevented by eating a proper diet focusing on calcium and sodium. Create healthy guidelines for your diet, supplements, and exercise alongside your doctor. During and after treatment, take vitamin D, as it helps strengthen bones. 

In most cases, the cause of thyroid cancer is not determined. If you have a family history of medullary thyroid cancer or experience any new symptoms, talk to your doctor. If you live near a nuclear power plant, talk to your doctor about potassium pills. 

There are several risks associated with goiter.

Goiters can occur at any age, though it is more common in people in their 40s. The following face a higher risk of goiter:

• Lack of iodine-rich food is a risk factor for goiter. Iodine is found in iodized salt, seafood, and seaweed. This explains why goiter is somewhat more common in populations living in inland or mountainous regions.
• Goiter tends to strike females due to their additional risk of having thyroid disorders.
• Those with a medical or family history of autoimmune diseases
• Pregnant women and those undergoing menopause, though the exact cause is not clear
• Radiation exposure or treatments in the neck or chest, or occupational exposure from nuclear facility and X-ray centers
• Use of medicines such as immunosuppressants, antiretrovirals, the heart drug amiodarone (Cordarone, Pacerone, others), and the psychiatric drug lithium (Lithobid, others)

Possible complications:

• Hypothyroidism: Goiter-destruction of the thyroid gland by an auto-immune disease leads to lower production in the thyroid gland. In response to this, the body releases more thyroid-stimulating hormones from the pituitary, which stimulates growth of the thyroid and can cause goiter.
  • Heart problems: Hypothyroidism may cause increased accumulation of density lipoprotein, which may increase the risk of heart disease. If hypothyroidism persists, it can cause enlargement and/or failure of the heart.
  • Peripheral neuropathy: Long-term hypothyroidism can damage the peripheral nerves.
  • Mental health: In the early stage of hypothyroidism, mental functioning may become slow and grow severe over time.
  • Birth defects: Higher risks of birth defects are associated with mothers who have untreated thyroid disease. Such babies are also prone to intellectual and developmental problems. Babies with hypothyroidism, if untreated, are at risk of problems with physical and mental development. If the condition is diagnosed and managed within the first few months of life, there is a chance of improvement in normal development.
• Hyperthyroidism: Excessive stimulation of hormone production leads to enlargement of the thyroid gland.
  • Heart problems: Increased thyroid hormones can cause atrial fibrillation, congestive heart failure, and tachycardia
  • Osteoporosis: Osteoporosis can occur due to long-term elevation of thyroid hormone levels
  • Skin problems: Some patients may develop dermopathy, which causes redness and swelling of the shins and feet.
  • Eye problems: Some patients may develop eye disorders, which cause bulging, red, or swollen eyes, and sensitivity to light. They may also experience visual disturbances.
  • Thyrotoxic crisis: Symptoms may suddenly intensify, leading to fever, tachycardia, and even delirium.