Hypothyroidism Flashcards
Etiology?
Without goiter: Congenital agenesis Radio idoine therapy Withdrawn thyroid treatment Idiopathic Treatment with alpha interferon Pulmonary hypertension patient 22% cause hypothyroidism With goiter: Hashimoto thyroids Drug induce: lithium, ptu, methimazole, endemic iodine deficiency Inborn error Goitrogenic food like turnip
Secondary and tertiary?
Secondary due to pituitary
Tertiary due to hypothalamic
Most common cause of hypothyroidism?
Atrophic hypothyroidism
What is hashimoto?
Autoimmune thyroiditis with atrophic changes with regeneration male to female 6:1 associated with other autoimmune conditions like mysthenia gravis, ceilic disease, Sjögren’s syndrome,
Antithyroid peroxidase or anti thyroglobulin antibodies rise
Clinical features?
Early: lethargy, malaise, weakness, muscle cramp, cold intolerance, constipation, dry skin, headache and menorrhagia brittle nails and delayed reflexes
Late: slow speech absence of sweating consipation peripheral edema pallar hoarsness decreased sense of taste and smell
Physical signs?
Pallor, puffiness, outer halves of eyebrow thin, cardiac enlargement, diastolic hypertension. Hyponatremia, thickening of tongue
Investigations?
Serum T4 low Serum t3 not distinguish between eu and hypo Serum tsh raise more than 20mu/I Increase circulating antibodies Serum cholesterol high Normocytic or macrocytic anemia
Complications?
Coronary artery disease Increase risk of infection Megacolon Myxedema Infertility rare Myxedema coma
Management?
Start with 50ug thyroxine for 3weeks Then 100ug for 3weeks Then 150ug for wholelife In IHD patient b blocker and vasodilator also give In pregnant: 50ug more than normal
What is myxedema coma?
State of depressed conciousness or coma due to severe hypothyroidism
Features: hypo=thermia and glycemia natremia and confusion coma
Management of myxedema?
Iv thyroxine not available so T3 2.5 ug then start thyroxine if concious patient
