Overproduction of thyroid hormones by thyroid gland

Demographics

• F>M
• Graves disease (autoimmune): 20-30 years
• Toxic adenoma: 30-50 years
• Toxic multinodular goitre (MNG): >50 years

Aetiology

• Hyperfunctioning thyroid gland:

  Graves Disease

  • Toxic multinodular goitre
  • TSH-producing pituitary adeonma
  • Thyroiditis - subacute granulomatous, hashimotos, silent lymphocytic
  • Contrast induced thyroiditis

• Destruction of the thyroid gland - causes stored thyroid hormone to leak out

  • Thyroiditis - subacute granulomatous, hashimotos, silent lymphocytic
  • Drug-induced thyroiditis (amiodarone, lithium)
  • Contrast induced thyroiditis
  • Radiation thyroiditis

Pathophysiology

B/T cell autoimmunity → produce IgG Ab → Ab binds to TSH receptor → increases thyroid hormone production and causes thyroid gland hyperplasia

Risk Factors

• Graves’ disease family history