A 29-year-old woman complains of nervousness and muscle weakness of 6 months in duration. She is intolerant of heat and sweats excessively. She has lost 9 kg (20 lb pounds) over past 6 months, despite increased caloric intake. She frequently finds her hea racing and can feel it pounding in her chest. She also states that she has missed several menstrual periods over past few months. Physical examination reveals warm and moist skin and bulging eyes (exophthalmos). Laboratory studies will likely reveal which of the following endocrine abnormalities in this patient?
High-Yield Explanation
- Given features suggests the diagnosis of Graves disease - It is autoimmune disorder caused d/t development of autoimmune antibodies against TSH receptors. - Graves disease is most frequent cause of hypehyroidism in young adults. - It is characterized by diffuse goiter, hypehyroidism & exophthalmos. - Anti-thyroid DNA antibodies (choice A) are not common in patients with Graves disease - Thyroid shows increased uptake of radioactive iodine in graves disease (choice C is wrong). - Serum levels of TSH are low (see choice D) & T3, T4 levels are high d/t stimulation of TSH receptors by TSIg.