Euthyroid sick syndrome

Catabolic hormones release Euthyroid-sick syndrome... 

Kotake Y, Matsumoto M, Takeda J. Thiopental intensifies the euthyroid sick syndrome after cardiopulmonary resuscitation. J Anesth 20(X) 14(1 ) 38—41. 

A progressive spectrum of thyroid test result anomalies accompanies NTIs in euthyroid patients (the euthyroid sick syndrome )(Figure 52-6 and Box 52-5). The earliest and most common changes that occur are a reduction in the serum concentrations of total and free Tj, sometimes to extremely low concentrations, and an elevation in the serum concentration of rT (the lowTj state ). These changes have been ascribed to a block in the 5 deiodinases that convert T4 to T3 in peripheral tissue. Acute and chronic nutritional problems, poorly controlled diabetes meUitus, and drugs such as hydrocortisone and beta blockers can also inhibit this conversion. 

Reverse T3 in serum is present almost entirely as a result of its generation from T4 in peripheral tissues by 5-deiodinases. The concentration of serum rT3 is lower than that of Ts because of the faster metabolic clearance of rTs. Serum rT3 concentrations are elevated at birth, but decrease to stable values by about the fifth day of life. Reverse T3 in amniotic fluid decreases with increasing gestational age. The use of reverse Ts in patients with the euthyroid sick syndrome has fallen out of favor with the recognition that rTs is not always elevated in iUness. Specifically, renal failure is associated with low rTs concentrations. 

Chopra IJ. Cfinical review 86 Euthyroid sick syndrome is it a misnomer J Clin Endocrinol Metab 1997 82 329-34. 

Mclver B. Euthyroid sick syndrome An overview. Thyroid 1997 7 125-32. 

Wartofsky L, Burman KD. Alterations in thyroid function in patients with systemic illness The euthyroid sick syndrome. Endocr Rev 1982 3 164-217. 

The degree and extent of the abnormality in thyroid function generally correlates with the severity of the nonthyroidal illness. These conditions are frequently referred to as the euthyroid sick syndrome. It is likely that these changes represent adaptive forms of hypothyroidism that serve to reduce the availability of thyroid hormones to lessen the impact of the nonthyroidal Ulness. ... 

TFIls Exclude hyperthyroidism May show euthyroid sick syndrome (iT3/T4 and TrT3). This reverses with weight gain. 

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