A review of literature on thyroid hormone disorders originated from extra thyroidal illness

Abstract

The definition of non-thyroidal illness arises from the fact that thyroid hormones within blood circulation is reduced not due to the malfunction of thyroid organ, but it is mamifested from disorders of other organs. Clinical conditions such as cardiovascular diseases mainly myocardial infraction, sepsis, surgery and many other chronic and sever diseases are associated with thyroid hormones reduction. Serum T3 concentration is reduced during non-thyroidal illness, but serum T4 concentration is seemed to be raised in most of the cases, which is due to the inhibition of T4 conversion into T3 as result of reduced activity of deidoniase enzyme. It seems the reduction in the T3 concentration do not exhibit neither any negative side effects in metabolism nor any irreversible harm in patient involved. There is not any suggestion that hypothyroidism originated from non-thyroidal illness can be rapidly leads to fatal outcome but such low reduction in thyrod hormones and particularly T3 can be considered as a key factor for the initiating the medical attendance and the necessary steps to prevent further clinical complication. © Asian Network for Scientific Information.