Hyperthyroidism
A 24-years old woman was found to have mild hyperthyroidism due to Graves disease. She appears to be in good health otherwise.
Questions and tasks:
1. Describe briefly the symptoms of hyperthyroidism!
2. In Graves disease, the cause of the hyperthyroidism is the production of an antibody that does which of the following:
a. activates the pituitary thyrotropin-releasing hormone (TRH) receptor and stimulates TSH release
b. activates the thyroid gland TSH receptor and stimulates thyroid hormone synthesis and release
c. activates thyroid hormone receptors in peripheral tissues
d. binds to thyroid gland thyroglobulin and accelerates its proteolysis and the release of its supply of T4 and T3
e. binds to thyroid-binding globulin (TBG) and displaces bound T4 and T3
3. The decision is made to begin treatment with methimazole. Methimazole reduces serum concentration of T3 primarily by which of the following mechanisms?
a. accelerating the peripheral metabolism of T3
b. inhibiting the proteolysis of thyroid-binding globulin
c. inhibiting the secretion of TSH
d. inhibiting the uptake of iodide by cells in the thyroid
e. preventing the addition of iodine to thyrosine residues on thyroglobulin
4. Though rare, a serious toxicity associated with thionamides is which of the following?
a. accelerating the peripheral metabolism of T3
b. inhibiting the proteolysis of thyroid-binding globulin
c. inhibiting the secretion of TSH
d. inhibiting the uptake of iodide by cells in the thyroid
e. preventing the addition of iodine to thyrosine residues on thyroglobulin
After several years of treatment, the patient had run out of methimazol 2 weeks earlier from unknown reasons. She was presented to emergency department with tachycardia, shortness of breath, and chest pain. During last two days the shortness of breath, diarrhea, anxiety, and sweating were major symptoms. A TSH measurement revealed a value of <0.01 mIU/L (normal 0.4-4.0 mIU/L).
5. Which diagnosis would you make on available data?
6. Which of the following drugs is the most useful adjuvant treatment of this clinical condition?
a. Amiodarone
b. Betamethasone
c. Epinephrine
d. Propranolol
e. Radioactive iodine