Influence of Nonthyroidal Illnesses on Serum Thyroid Hormone Indices in Hyperthyroidism
AUTOR(ES)
Lum, Steven M. C.
RESUMO
Severe intercurrent nonthyroidal illnesses (diabetic ketoacidosis, myocardial infarction, fulminant hepatitis and bacterial pneumonia) in four thyrotoxic patients were associated with depression of total serum thyroxine (T4) and triiodothyronine (T3) values into the normal or even subnormal range. A diagnosis of hyperthyroidism was established by a combination of elevated radioactive iodine uptake, absent thyroid-stimulating hormone response to thyrotropin-releasing hormone or an elevated free T4 by dialysis values. In the two of four cases that had a fatal outcome, there was a progressive decline in total T4 and total T3 values. In contrast, the two surviving patients had a progressive increase of total T3 and total T4 values into the hyperthyroid range as their underlying illness resolved. As has been seen with severe nonthyroidal illnesses, pronounced depression of total T3 and total T4 levels in hyperthyroid patients may also portend a poor prognosis.
