Euthyroid Sick Syndrome

To the Editor: In a recent clinicopathological conference,¹ a diagnosis of primary hypothyroidism was apparently established by the findings on physical examination and laboratory studies. Dr. Jacob Lerman noted in the discussion of the case that although the serum thyroxine and tri-iodothyronine values were low, the patient was probably not severely hypothyroid. However, in the absence of an elevated thyrotropin value, it is quite possible that this patient was not hypothyroid at all but rather “sick euthyroid.”² Abnormal thyroid-function tests have been described in euthyroid patients with a wide variety of systemic illnesses.^{2 3 4 5 6} The tri-iodothyronine is decreased, the thyroxine is. No extract is available for articles shorter than 400 words.