RT Book, Section A1 Fisher, Delbert A. A2 Rudolph, Colin D. A2 Rudolph, Abraham M. A2 Lister, George E. A2 First, Lewis R. A2 Gershon, Anne A. SR Print(0) ID 7053468 T1 Chapter 530. Other Disorders of the Thyroid T2 Rudolph's Pediatrics, 22e YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-149723-7 LK accesspediatrics.mhmedical.com/content.aspx?aid=7053468 RD 2024/03/29 AB Nonthyroidal illness (NTI) was initially characterized as a selective deficiency of serum and tissue T3 (triiodothyronine) in patients dying with severe prolonged illness.This syndrome of low total and free serum T3, normal, low or high total serum T4 (thyroxine), increased T4 sulfate, normal to high free T4, and normal serum thyroid-stimulating hormone (TSH) concentrations has now been reported in a variety of situations. These include the premature neonate (see Chapter 527) patients with protein-calorie malnutrition or anorexia nervosa, fasting subjects, postoperative patients, and patients with a variety of severe acute and chronic illnesses. The latter have included patients with diabetic ketoacidosis, severe trauma, burns, febrile states, cirrhosis, and renal failure. In addition, a number of drugs have been observed to produce a similar syndrome; these drugs include dexamethasone, selected radiographic contrast agents, propylthiouracil, propranolol, and amiodarone. There is no convincing evidence that treatment with thyroid hormones, either T4 or T3, is effective in most patients with nonthyroidal illness. Treatment should be directed to the primary systemic illness. There is some evidence to suggest that treatment may be beneficial in selected clinical conditions such as postoperative cardiac surgery.