Final answer:
Thyroid stimulating hormone (TSH) levels are suppressed in all of the following except Graves' disease.
Step-by-step explanation:
Thyroid stimulating hormone (TSH) levels are suppressed in all of the following except:
a) Graves' disease.
b) Autonomous toxic nodule.
c) Acute viral thyroiditis.
d) Subacute hypothyroidism.
TSH is released from the anterior pituitary in response to thyrotropin-releasing hormone (TRH) from the hypothalamus. In Graves' disease, thyroid-stimulating immunoglobulin (TSI) stimulates the thyroid to make too much thyroid hormone, leading to hyperthyroidism. Thus, TSH levels are suppressed in Graves' disease.