HYPOTHYROIDISM AND HYPERTHYROIDISM SHAHIDA PERVEEN, AMBREEN Post RN BSCN Semester II FACULTY SIR RAJA April 13, 016
Objectives: State the functions of thyroid hormone. Understand the pathologic mechanism of hypothyroidism interim of : Cretinism Myxedema Hashimoto s disease Understand the pathologic mechanism of hyperthyroidism interim of: Graves disease Thyroid storm
Thyroid hormone Thyroid hormone increases the metabolism and protein synthesis in almost all body tissues. It is also necessary for brain development and growth in infants for 6 months
Hypothyroidism Hypothyroidism can occur as a Congenital Acquired
Congenital Hypothyroidism Causes lack of TSH Abnormal biosynthesis of thyroid hormone Congenital Hypothyroidism is the cause of preventable mental retardation It is present at birth The manifestations of untreated is referred as cretinism
Conti Untreated congenital hypothyroidism impairs body growth and mental retardation Antithyroid drugs Carbimazole and methimazole Antithyroid drugs Carbimazole and methimazole can easily cross the placenta and block the fetal thyroid function
Acquired Hypothyroidism/ Myxedema Hypothyroidism in adults causes the Myxedema Slow the metabolic process Non pitting edema It is normal and few sign and symptoms Myedematous coma is life threating Myedematous coma is dysfunction of thyroid gland
Conti. Causes Thyriodectomy Lithium bicarbonate Carbimazole and methimazole Amiodarone
Myxedema
Hashimoto s thyrioditis Hakaru Hashimoto, a Japanese surgeon working in Berlin, Germany. His report, published in 1912 It is most commonly caused by autoimmune Thyroid gland may be totally destroyed by immunologic process It is major cause of goiter and hypothyroidism
Sign and symptoms of Hypothyroidism Fatigue Depression Weight gain Cold intolerance Excessive sleepiness Dry, coarse hair Constipation Dry skin Muscle cramps Increased cholesterol levels Decreased concentration Vague aches and pains Swelling of the legs
Hyperthyroidism Hyperthyroidism (Thyrotoxicosis) is the clinical syndrome that result when tissues are exposed to high level of circulating thyroid hormone. Most common cause of hyperthyroidism is Graves disease and others are, Multinodular goiter, adenoma of thyroid, Drug amiodarone and thyriditis.
Cont T4 and T3 are produced in thyroid gland but T3 is the active component. T3 can also come form T4. T4-to-T3 conversion is stopped by starvation, liver disease and certain drugs (propylthiouracil, propranolol, prednisone) T4 and T3 are circulating as bound proteins-tbg (thyroid binding globulin) If TBG goes up-t4 and T3 would go up. If TBG goes down-t4 and T3 would go down.
PATHO PHYSIOLOGY
Graves disease Graves disease is a state of hyperthyroidism, goiter it is an autoimmune disorder characterized by abnormal stimulation of thyroid gland by thyroid stimulating antibodies (TSH receptor antibodies) that act through the normal TSH receptors It is five times more common in females
Thyroid storm Thyroid storm, also referred to as thyrotoxic crisis, is an extreme and life-threatening form of thyrotoxicosis, induced by excessive release of thyroid hormones (THs). The clinical presentation includes fever, tachycardia, hypertension, and neurological (agitation, restlessness) and mortality rate is high.
Sign and symptoms of hyperthyroidism
Indications for surgery Patients with very large goiters Goiters causing upper airway obstruction or severe dysphagia In a patient who also has a nonfunctional thyroid nodule, which can be a thyroid cancer, surgery can both cure the hyperthyroidism and remove the nodule. Moderate to severe Graves' ophthalmopathy, Pregnant women who are allergic to antithyroid drugs and/or are tolerating hyperthyroidism poorly
References: Porth, M. C. (2002). Pathophysiology: Concepts of Altered Health Sciences. (6 th ED). USA: New York. Lippincott Williams &Wilkins