Which thyroid diseases cause hyperfunction or hypofunction?
Hyperfunction of the thyroid is caused by autonomy (single or multiple thyroid nodules) or by an autoimmune thyroid disease with or without eye involvement = Graves' disease. Hyper-function may also be caused through intake of too many thyroid hormone tablets.
Hypothyroidism is a thyroid hormone deficiency, which may be caused by a reduced production due to an autoimmune disease such as Hashimoto thyroiditis, or it may be as a result of thyroid surgery or after radioiodine treatment of the thyroid, by a malformation of the thyroid gland or due to a longstanding iodine deficiency and goiter.
