Thyroid Disorders Flashcards
What are the two types of goiter?
Endemic : Caused by lack of iodine in the diet
Sporadic: drugs – Propylthiouracil, lithium, iodides, Foods – rutabagas, cabbage, soybeans, peanuts, peaches, peas, strawberries, spinach and radishes
What is a goiter?
Occurs when the thyroid gland is unable to secrete enough thyroid hormone to meet metabolic needs. Hyperplasia is caused by chronic stimulation via elevation TSH
What are the symptoms of a goiter?
Monotone voice, Dysphagia (difficulty swallowing), Tracheal compression
How are goiters diagnosed and treated?
T3, T4 and TSH are usually normal. Thyroid Ultrasound for asymmetry or palpable nodules.
needle aspiration for fast growing goiters. Partial thyroidectomy for large goiters
What are the causes of primary hypothyroidism?
iodine deficiency, autoimmune (Hashimotos), iatrogenic (iodine therapy, thyroidectomy), post partum thyroiditis, drug induced (lithium, amiodarone, antithyroid), congenital
What are the causes of teritary hypothyroidism?
hypothalamus dysfunction, hemochromatosis, sarcoidosis
What are symptoms of hypothyroidism?
fatigue, cold intolerance, weakness, lethargy, weight gain, constipation, myalgias, arthalgias, menstrual irregularities, hair loss
What are signs of hypothyroidism?
dry, course skin., hoarse voice, brittle nails, periorbital/peripheral edema, delayed reflexes, bradycardia
How is hypothyroidism diagnosed?
TSH level is elevated, indicating thyroid hormone production is insufficient to meet metabolic demands, and free thyroid hormone levels are depressed.
How is hypothyroidism treated?
100-200mg Levothyroxine (T4) daily. Start at 25-50mcg daily for elderly and slowly increase. Take on empty stomach. monitor clinical features, TSH (for patients w/intact hypothalamic-pituitary axis), Free T4 (for patients with pituitary insufficiency)
How does age effect medication dosage for hypothyroidism?
stable dosing until 7th decade: With age, thyroid binding may decrease, and the serum albumin level may decline. Levothyroxine dosage may need to be reduced by up to 20 percent
What is hashimoto’s thyroiditis?
“Chronic lymphocytic thyroiditis.” Can be associated with non-Hodgkins lymphoma. automimmune hypothyroidism. more common in women btw 30-60.
What are clinical findings associated with Hashimoto’s?
Goiter, low hormone levels. Increased number of antibodies to the enzyme, thyroid peroxidase. Anti-thyroid peroxidase (anti-TPO) antibodies
What are symptoms of Hashimotos?
painless goiter, fatigue, muscle weakness, weight gain, feeling of fullness in the throat, neck pain, low-grade fever
What is the treatment of Hashimoto’s?
Levothyroxine (T4) (Levothyroid, Synthroid): 50-100mcg daily – under 60 w/o CAD. 100-150mcg daily – pregnant women. 12.5-50mcg daily – over 60 or pts with CAD. Monitor TSH
What is subclinical hypothyroidism?
no symptoms or minimal symptoms suggestive of hypothyroidism with normal serum free T4 and T3 and elevated serum TSH concentrations
What are strong predictors of subclinical hypothyroidism progressing to overt hypothyroidism?
anti-TPO antibodies, TSH>20, radioiodine ablation Hx (Graves Dz), or other radiation therapies.
What is myxedema?
develops in older adults. droopy eyelids, lethargy, fatigue, mental sluggishness, decreased reflexes. mucopolysaccharide infiltration of the dermal space causes facial puffiness, periorbital edema, non-pitting pretibial edema
How is myxedema treated?
Levothyroxine (T4) (Levothroid, Synthroid)
50-100mcg daily – under 60 w/o CAD
100-150mcg daily – pregnant women
12.5-50mcg daily – over 60 or pts with CAD. Monitor TSH
What is a myxedema coma?
life-threatening end-stage expression of hypothyroidism. Occurs most frequently in elderly women w/hypothyroidism and may be caused by stress, cold, narcotics, or discontinuation of therapy