euthyroid sick syndrome

Also found in: Dictionary, Wikipedia.

eu·thy·roid sick syn·drome

abnormalities in levels of hormones and function tests related to the thyroid gland occurring in patients with severe systemic disease. Thyroid function is actually normal in these patients, and it is uncertain whether treatment of these abnormalities would be beneficial.

euthyroid sick syndrome

Lab medicine A “condition” in Pts who are critically ill with nonthyroid diseases that alter serum levels of thyroid hormones which, in absence of underlying nonthyroid illness, would be correctly interpreted as indicating a disease of the thyroid 'axis' Lab Peripheral ↓/inhibition of 5'-deiodinase, the deiodination enzyme, resulting in ↓ peripheral 5'-monodeiodination of thyroxine–T4, reversed, free, and total T3; TSH, TRH, and usually free thyroxine levels are normal. See Hyperthyroidism, Hypothyroidism.

euthyroid sick syndrome

Any derangement in thyroid hormone blood levels in patients affected by another (usually critical) illness. The altered levels of thyroid hormones are not caused by primary thyroid dysfunction; they return to normal when the underlying illness is successfully treated.


having a normally functioning thyroid gland.

euthyroid sick syndrome
a euthyroid state in which extrathyroidal factors cause a reduction of serum T3 or T4 and elevation of reverse T3 levels. Seen in patients with systemic illness, trauma, fever, starvation, treatment with glucocorticoids, etc. May be a protective metabolic effect.
References in periodicals archive ?
Euthyroid sick syndrome was characterized as low FT4, FT3 and TSH levels.
Euthyroid sick syndrome was documented in 86 ICU patients (17%); 16% were medical ICU patients, while 19.
Euthyroid sick syndrome was documented in 16% of medical ICU patients compared with the 19.
Euthyroid sick syndrome in meningococcal sepsis: the impact of peripheral thyroid hormone metabolism and binding proteins.
4] Graves disease High High High Multinodular goiter High High High Hyperthyroidism in High High High pregnancy Subacute thyroiditis High, normal High, normal High, normal Trophoblastic tumors High High High T3 toxicosis Normal High Normal Neonatal hyperthyroidism High High High Primary hypothyroidism Low Low, normal Low Secondary hypothyroidism Low Low Low Tertiary hypothyrodism Low Low Low Euthyroid sick syndrome Low, normal Low Low, normal Laboratory evaluation of thyroid function Pathological condition [FT.
added that there is no role for T3 in the treatment of the euthyroid sick syndrome, either.
Euthyroid sick syndrome in trauma patients with severe inflammatory response syndrome.