Thyrotoxicosis refers to an elevated concentration of thyroid
hormone as well as the related clinical manifestations. This is
differentiated from thyroid storm, a life-threatening
manifestation of thyrotoxicosis in which a markedly
hypermetabolic state is present. Hyperthyroidism most commonly
results from uncontrolled Graves disease, in which
autoantibodies to the TSH receptor are produced. This leads to
excessive thyroid hormone production from the thyroid gland and
a reflexive inhibition of TSH release from the pituitary gland.
Other etiologies can include a solitary thyroid adenoma, toxic
multinodular goiter, hypersecretory thyroid carcinoma,
thyrotropin-secreting pituitary adenoma, struma ovarii, and
iodine or amiodarone administration. A precipitating event, such
as surgery, trauma, myocardial infarction, pulmonary embolism,
diabetic ketoacidosis, childbirth, severe infection,
discontinuation of antithyroid medication, or thyroid surgery on
a patient with uncontrolled hyperthyroidism, is often needed to