Multinodular Goiter

Overview and Symptoms

A multinodular goiter is an enlarged thyroid caused by multiple thyroid nodules. Multinodular goiters can be either toxic (makes too much thyroid hormone and causes hyperthyroidism) or non-toxic (does not make too much thyroid hormone). It is not known what causes multinodular goiters in most cases, but iodine deficiency (i.e. too little iodine in the diet) and certain genetic factors have been shown to lead to multinodular goiters.

Most multinodular goiters are not toxic and do not cause symptoms. Patients with a multinodular goiter would show symptoms of hyperthyroidism, which include:

• Nervousness and irritability
• Increased resting heart rate
• Heat intolerance and increased sweating
• Tremor
• Weight loss or changes in appetite
• Frequent bowel movements
• Sudden paralysis
• Thyroid enlargement (lump in the neck)
• Thick redness on the front of legs, which occurs with Graves' Disease
• Thin, delicate skin and irregular fingernail and hair growth
• Decreased menstrual flow
• Impaired fertility
• Mental disturbances
• Sleep disturbances (including insomnia)

Diagnosis

Your doctor will take a complete healthy history and physical exam. He/she will also perform a thyroid ultrasound, which is the best test to look at the thyroid and will allow the doctor to see the size of the thyroid and specific features of the nodules.

If your doctor suspects the multinodular goiter may be cancerous, you will have a fine-needle aspiration biopsy (FNAB). In this test, a small needle (like the needles used for drawing blood) is placed into the nodule either by ultrasound guidance or feeling the nodule with the fingers. Cells are removed from the nodule into the needle and examined under the microscope.