Introduction
A goiter is a lump or swelling that appears at the front of the neck. It is actually an enlargement or nodule on the thyroid gland that can result from a variety of conditions. Your thyroid gland produces hormones that are essential for good health and energy. Although not all goiters affect hormone production, you should have any lump or neck swelling checked out by your doctor. If necessary, goiters are removed with surgery.
Anatomy
Your thyroid gland is located in the front lower part of your neck, in front of your windpipe. Your thyroid produces two thyroid hormones called thyroxine (T4) and triiodothyronine (T3). The thyroid hormones travel throughout your body in your bloodstream, regulating the function of your cells and tissues. T4 and T3 help control your body’s metabolism and energy levels. These hormones help regulate how fast your heart beats and how quickly you burn calories.
The hypothalamus and pituitary gland in your brain regulate T4 and T3 production. When T4 and T3 levels are low, the hypothalamus produces thyrotropin-releasing hormone (TRH) to signal the pituitary gland to produce thyroid stimulating hormone (TSH). The TSH travels in the bloodstream and signals the thyroid gland to produce more T4 and T3. When T4 and T3 levels are high, the pituitary gland stops producing TSH.
Causes
There are several causes and types of goiters. In some cases, the cause of goiter is unknown, and in others there can be a hereditary component. The entire gland may be enlarged (diffuse goiter) or the gland may have one or more nodules. Some of the more frequent causes are listed below.
Iodine Deficiency
A simple endemic (colloid) goiter may be caused by a lack of iodine in the diet, but this is rare in the United States. It is more common in underdeveloped countries where people lack iodine in their diets. In people with iodine deficiency, the thyroid gland does not produce enough hormones and an overproduction of TSH occurs that causes the thyroid gland to enlarge.
Graves Disease
Graves Disease is an autoimmune disorder in which the thyroid gland produces too much T4 causing the thyroid gland to enlarge.
Hashimoto’s Disease (Chronic Lymphocytic Thyroiditis)
Hashimoto’s Disease is an autoimmune disorder that causes thyroid gland inflammation and enlargement. Irregularities in thyroid hormone production cause the pituitary gland to produce too much TSH.
Thyroid Cancer
Thyroid cancer is not very common. It frequently appears as an enlargement on one side of the thyroid.
Pregnancy
Human chorionic gonadotropin (HCG) produced during pregnancy may cause a slightly enlarged thyroid gland.
Thyroiditis
Thyroiditis causes inflammation and enlargement of the thyroid gland. It may cause an over or underproduction of thyroid hormones. Thyroiditis may cause the thyroid gland to feel painful. The pain may increase with swallowing or pressure.
Lithium
The prescription medication lithium can create changes in thyroid function that lead to goiter.
Symptoms
The hallmark symptom of goiter is an enlarged thyroid gland. The entire gland may appear swollen or a lump or nodules may be visible. You may feel neck pressure or swelling. You may experience coughing, wheezing, or trouble swallowing or breathing. Some people may feel dizzy when raising their arms because of neck vein swelling.
Diagnosis
Your doctor can diagnose goiter by reviewing your medical history and examining your neck. Blood tests and imaging tests may be used to learn more about your thyroid gland. In some cases, a biopsy may be taken.
The most common blood tests are the Thyroid-stimulating hormone (TSH) assay and the Thyroxine (T4) measurement. The Thyroid-stimulating hormone (TSH) assay is used to determine if the thyroid gland is functioning properly. It can identify if an underactive gland is caused by a problem with the pituitary gland, hypothalamus, or a damaged thyroid gland. The Thyroxine (T4) measurement assesses thyroid functioning by testing how much T4 is in the blood. If the Thyroid-stimulating hormone (TSH) assay and the Thyroxine (T4) measurement are not normal, an Antithyroid Antibody Test is used to determine the presence of Hashimoto’s Disease.
On occasion, a doctor may order a Thyroid Ultrasound or a Thyroid Scan and Radioactive Iodine Uptake (RAIU) Test. Thyroid scans are used to identify how the thyroid gland is functioning and specify areas of overactivity or underactivity. Further, it can help determine if thyroid nodules or cancer are present. Fine-needle aspiration or a core biopsy using a larger needle may be used to obtain samples of the goiter. A biopsy may be taken if cancer is suspected. Your doctor may order additional types of imaging tests if necessary.
Treatment
Some types of goiter may go away without treatment, but it is important to have your doctor make that determination. The type of treatment that you receive depends on the cause, size, symptoms, and type of your goiter. Taking iodine or potassium iodine may help people with an iodine deficiency. Thyroid hormones may help to reduce your goiter and treat thyroid disorders. Radioactive iodine therapy is controversial. Surgery, a thyroidectomy, is used to remove the thyroid if other treatments fail, if the goiter is causing compression, or if cancer is present. Following radioactive iodine therapy or surgery, people will need to take thyroid hormone replacements for life.
Prevention
Diets in the US typically contain enough iodized table salt that iodine deficiency is not a concern. You should contact your doctor if you notice a lump or swelling on your neck. A thyroid examination should be part of your regular yearly physical examination.
Am I at Risk
Goiter occurs four times more often in women than in men. Goiters most frequently develop in people over the age of 40, and the risk increases with age. People with iodine deficiency have an increased risk of goiter.
Complications
Certain conditions associated with goiters may cause the thyroid gland to stop producing hormones and result in hypothyroidism. Alternatively, a goiter may be toxic and cause the thyroid gland to produce too much hormone, resulting in hyperthyroidism. Such conditions are usually treated with lifelong thyroid medications.
Copyright © - iHealthSpot Interactive - www.iHealthSpot.com
This information is intended for educational and informational purposes only. It should not be used in place of an individual consultation or examination or replace the advice of your health care professional and should not be relied upon to determine diagnosis or course of treatment.
The iHealthSpot patient education library was written collaboratively by the iHealthSpot editorial team which includes Senior Medical Authors Dr. Mary Car-Blanchard, OTD/OTR/L and Valerie K. Clark, and the following editorial advisors: Steve Meadows, MD, Ernie F. Soto, DDS, Ronald J. Glatzer, MD, Jonathan Rosenberg, MD, Christopher M. Nolte, MD, David Applebaum, MD, Jonathan M. Tarrash, MD, and Paula Soto, RN/BSN. This content complies with the HONcode standard for trustworthy health information. The library commenced development on September 1, 2005 with the latest update/addition on February 16, 2022. For information on iHealthSpot’s other services including medical website design, visit www.iHealthSpot.com.
