Colloid nodular goiter

Alternative names:

endemic goiter

Definition:

An enlargement of the thyroid gland, caused by inadequate iodine in diet, which is not associated with inflammation or cancer.

Causes, incidence, and risk factors:

A colloid nodular goiter occurs when the thyroid gland is unable to meet the metabolic demands of the body through sufficient hormone production. The thyroid gland compensates by enlarging which usually overcomes mild deficiencies of thyroid hormone. Colloid nodular goiters are also known as endemic goiters and are usually caused by inadequate dietary iodine (iodine in diet) and occur in certain geographical areas with iodine depleted soil, usually areas away from the sea coast. In the U.S., the Great Lakes, Midwest, and Intermountain regions are known as the "goiter belt". The use of iodized table salt prevents this deficiency. The incidence of iodine deficiency is now rare in the U.S. as a result of widespread distribution of foods from iodine sufficient areas. Risk factors are being a female, over 40 years old, having an inadequate dietary intake of iodine, residence in an endemic area, and a family history of goiters.