The word goiter simply refers to an enlarged thyroid gland. According to the American Thyroid Association (ATA), this enlargement, in most cases, is a physical sign that there is a condition making the thyroid grow abnormally – not that it’s not working properly. With that being said, however, goiters still can be present in patients with hyperthyroidism and hypothyroidism.
In most cases, goiters are caused by iodine deficiency. However, such is not the case in the United States. Instead, Hashimoto’s thyroiditis or Graves’ disease are the more common causes for this side of the world. In Hashimoto’s thyroiditis, the ATA reports that this condition actually destroys the patient’s own immune system. Of course, as time goes on, more wear and tear on this gland occurs until it cannot produce enough hormones for the body. The pituitary gland senses the low level of hormones and reacts, sending TSH, which activates the thyroid to do what it cannot at this point – produce hormones. This irritates the thyroid gland and causes it to grow, which likely causes the goiter.
In Graves’ disease, the ATA reports that while your own immune system is producing a protein (thyroid stimulating immunoglobulin or TSI), it also is making too much thyroid hormone. The pituitary gland detects the high levels of thyroid hormone and stops secreting TSH – just the opposite of Hashimoto’s thyroiditis. Consequently, in the case of Graves' disease, it is thought that the cause of goiters is due to TSI levels and the overload of thyroid hormones in the system.
Multinodular goiters cause goiters too. As the name suggests, there may be one or more nodules or lumps within the thyroid. This usually can be discovered on a routine visit to the doctor during a physical examination. What is known about this condition is that most nodules are benign or noncancerous. A small portion, however, may contain cancerous cells. It is important to stress that when patients discover goiters of any kind, because cancer is a small possibility, a thorough examination is needed.