Subclinical Hyperthyroidism: Controversies in Management -- American Family Physician
نویسنده
چکیده
www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 431 ness, and anxiety may be present). Atrial fibrillation may be the primary manifestation of subclinical hyperthyroidism in elderly patients. Physical examination will not reveal an enlarged thyroid gland in most patients. The pathophysiology of subclinical hyperthyroidism relates to the sensitivity of the pituitary gland to respond to minor elevations in serum or tissue T4 and T3 levels. Although these levels remain within the normal range, minimal increases in these thyronines are sufficient not only to decrease the serum TSH level by several logarithms (from about 1.0 μU per mL [1.0 mU per L] to less than 0.01 μU per mL [0.01 mU per L]), but also to induce abnormalities in several organs, including the heart and bones. The normal range must be considered as a reference, but it is possible to have important pathophysiologic manifestations of altered T4 or T3 at the tissue level even though the peripheral serum thyronine levels are considered normal.
منابع مشابه
Update on subclinical hyperthyroidism.
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