Goiter - simple

Causes

There are different kinds of goiters.

• A simple goiter can occur for no known reason, or when the thyroid gland is not able to produce enough thyroid hormone to meet the body's needs. The thyroid gland makes up for this by becoming larger.
• Toxic nodular goiter involves an enlarged thyroid gland that contains a small, rounded growth or growths called nodules. These nodules produce too much thyroid hormone.

Iodine is needed to produce thyroid hormone.

• Simple goiters may occur in people who live in areas with iodine-poor soil. People in these areas might not get enough iodine in their diet.
• The use of iodized table salt in the United States today prevents a lack of iodine in the diet.

In most cases of simple goiter the cause is unknown. Sometimes, certain medications such as lithium or aminoglutethimide can cause a simple goiter.

Simple goiters are also more common in:

• Anyone over age 40
• People with a family history of goiter
• Females

Symptoms

The main symptom is a swollen thyroid gland. The size may range from a single small nodule to a large neck lump.

Some people with a simple goiter may have symptoms of an underactive thyroid gland.

Rarely, the swollen thyroid can put pressure on the windpipe and food pipe (esophagus), which can lead to:

• Breathing difficulties (may rarely occur with very large goiters)
• Cough
• Hoarseness
• Swallowing difficulties

Exams and Tests

The doctor will feel your neck as you swallow. The doctor may be able to feel swelling in the area.

With very large goiters, there may be swelling in the neck vein, and you may feel dizzy when you raise your arms above your head.

You may have the following blood tests to measure thyroid function:

• Free thyroxine (T4)
• Thyroid stimulating hormone (TSH)

Tests to look for abnormal, and possibly cancerous areas in the thyroid gland include:

• Thyroid scan and uptake
• Ultrasound of the thyroid

If nodules are found on an ultrasound, a biopsy should be done to check for thyroid cancer.

Treatment

A goiter only needs to be treated if it is causing symptoms.

Treatments for an enlarged thyroid include:

• Thyroid hormone replacement pills, if the goiter is due to an underactive thyroid
• Small doses of Lugol's iodine or potassium iodine solution if the goiter is due to a lack of iodine
• Radioactive iodine to shrink the gland, especially if the thyroid is producing too much thyroid hormone
• Surgery (thyroidectomy) to remove all or part of the gland

Outlook (Prognosis)

A simple goiter may disappear on its own, or may become larger. Over time, the thyroid gland may stop making enough thyroid hormone. This condition is called hypothyroidism.

Less commonly, a goiter may become toxic and produce thyroid hormone on its own. This can cause high levels of thyroid hormone, a condition called hyperthyroidism.

When to Contact a Medical Professional

Call your health care provider if you experience any swelling in the front of your neck or any other symptoms of goiter.

Prevention

The use of iodized table salt prevents most simple goiters.

Alternative Names

Simple goiter

References

Kim M, Ladenson P. Thyroid. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders; 2011:chap 233.

Schlumberger MJ, Filetti S, Hay ID. Nontoxic diffuse and nodular goiter and thyroid neoplasia. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, Pa: Saunders Elsevier;2011:chap 14.

Update Date: 6/4/2012

Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by Shehzad Topiwala, MD, Chief Consultant Endocrinologist, Premier Medical Associates, The Villaegs, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.