Thyroid Disorders

  1. Hyperthroidism
    • hyperfunction of the thyroid gland and exposure of tissues to excessive amounts of thyroid hormone paralleled by overactivity of the sympathetic nervous system
    • thyrotoxicosis: a hypermetabolic state induced by excessive release of thyroid hormone (not the sole cause)
  2. Hypothyroidism
    inadequate production of thyroid hormoneĀ 
  3. Risk Factors for thyroid disorders
    • Pregnancy
    • Family History of thyroid disease or any autoimmune disease
    • Current presentation w/autoimmune disease
    • History of taking anti-thyroid meds (to treat hyperthyroidism)
    • Previous treatment w/ radioactive iodine (for thyroid cancer)
    • Previous thyroid surgery
    • Exposure to radiation to neck or upper chest
  4. Thyrotoxicosis Epidemiology
    • subclincal individuals: show no history of thyroid disease, normal t4 levels, low TSH levels
    • Clinical individuals: high t4 levels, low TSH levels
    • women more likely to display abnormal TSH levels
    • main risk factors: age and sex
  5. Hypothyrodism Epidemiology
    • women more likely than men
    • subclinical more prevelant than clinical
    • main risk factors: age and sex
  6. Causes for Primary Hypothyroidism
    • Hashimoto's disease
    • Acquired (postablative) hypothyroidism
    • Drugs (lithium, iodides)
    • Iodine deficiency
    • Enzyme defects
    • Thyroid hypoplasia
    • Goitrogens
  7. Causes for Secondary Hypothyroidism
    • Pituitary disease
    • Hypothalamic disease (rare)
  8. Causes for Primary Hyperthyroidism (thyrotoxicosis) - Elevated RAIU
    • Grave's disease (diffuse toxic hyperplasia)
    • Hyperfunctioning multinodular goiter
    • Hyperfunctioning adenoma
    • Iodine-induced hyperthyroidism
    • Neonatal thyrotoxicosis ass. w/maternal Graves disease
  9. Causes for Secondary Hyperthyroidism (thyrotoxicosis) - Elveated RAIU
    • TSH-secreting pituitary adenoma (rare)
    • Pituitary resistance to thyroid hormone
  10. Causes for Thyrotoxicosis NOT associated w/ hyperfunctioning thyroid gland - Suppressed RAIU
    • Painful (granulomatous) thyroiditis
    • Painless (subacute) thyroiditis
    • Ectopic thyroid tissue (struma ovarii - ovarian teratoma; thyroid cancer)
    • Factitious thyrotoxicosis (exogenous thyroxine intake)
Card Set
Thyroid Disorders
Thyroid Disorders