Etiology of hyperthyroidism/thyrotoxicosis

• increased production of T4/T3 by thyroid gland

  • stimulation mediated through TSH rececptors

    • Graves disease

    • hyperthyroidism related to choriocarcinoma (which produces hCG, which binds to thyroid receptors with lower affinity than T4)

    • hyperthyroidism due to excessive pituitary TSH formation—relatively high TSH and thyroid hormone (these would be weird lab values. very rare)

  • autonomous thyroidal T4, T3 production

    • toxic multinodular goiter (Plummer disease)

    • toxic adenoma

    • thyroid carcinoma

• increased release

  • thyroiditis

• excess-iodine-induced (Jod-Basedow)

  • intake of iodine

  • drugs: amiodarone

• non-thyroidal source of T4/T3

  • excess T4 or T3 intake, as in inappropriate supplementation

  • struma ovarii, a teratoma of the ovary that contains active thyroid tissue

Category: Endocrinology Notes