Thyroiditis is caused by an attack on the thyroid, causing inflammation and damage to the thyroid cells. Antibodies that attack the thyroid cause most types of thyroiditis. As such, thyroiditis is often an autoimmune disease, like juvenile (type 1) diabetes and rheumatoid arthritis. It is not known why certain people make anti-thyroid antibodies, although this tends to run in families. Thyroiditis can also be caused by an infection, such as a virus or bacteria, which can also cause inflammation in the gland. Finally, drugs such as interferon and amiodarone, can also damage thyroid cells and cause thyroiditis.
