Anonymous
Basically, according to the Thyroid Source Book, Plummer’s Disease is ANOTHER thing that can cause hyperthyroidism. Graves is one cause, and it is an autoimmune disorder. But you can get goiter for various reasonss and a “toxic multinodular goiter” can cause it as well. In layman’s terms this is occurs when the thyroid, enlarged with goiter, has noticeable lumps and bumps (nodules) on it. In Plummer’s disease, these lumps develop the ability to produce their own thyroid hormone over time. So you have your thyroid producing thyroid hormone, and the nodules on the goiter producing the hormone. The nodules however do not respond at all to TSH levels, like your thyroid gland does. The pituitary stops producing TSH (to try to control thyroid hormone levels), and the thyroid itself lowers production. But the goiter nodules do not respond. They are out of control, and continue to produce the hormones, causing hyperthyroid symptoms.