triiodothyronine--reverse and Sepsis

In septic patients the clinical course of the disease is characterized by high DIT and rT3 serum concentrations as well as a low T3-syndrome. While rT3 is elevated in almost all critically ill patients, the increase in DIT is indicative of severe infection. Prolactin levels are regularly elevated in sepsis although to variable degrees. Catecholamines and vasopressin should be regarded as acute responders. The pattern of cortisol secretion is uncertain. In most situations the secretion appears to be elevated; the circadian rhythm is disturbed.

Topics: Adrenocorticotropic Hormone; Adult; Aged; Aged, 80 and over; Diiodothyronines; Hormones; Humans; Hydrocortisone; Middle Aged; Postoperative Complications; Prolactin; Sepsis; Shock, Septic; Thyrotropin; Thyroxine; Triiodothyronine; Triiodothyronine, Reverse; Vasopressins

Thyroid and pituitary function was studied in 10 male and 6 patients female during critical non-endocrine disease. Low concentrations of TT3 were observed in each case. Seven patients out of whom 3 survived, presented with low levels of TT4 due to deficiency in TBG in the presence of normal values of FTI and FT4, whereas a 'low T4-syndrome', characterized by low concentrations of both TT4 and FT4 was seen in 9 patients, 8 of whom died 1 to 16 days after evaluation of pituitary function. A diminished response of TSH to iv TRH (400 micrograms), as observed in 4 patients with normal FT4 and in all patients with 'low T4-syndrome', was not accompanied by a concomitant lack in stimulated release of LH, FSH and Pr1 in the majority of cases. However, the secretory maximum of LH and FSH following stimulation by LRH (100 micrograms iv) was delayed in 10 and in 9 patients, respectively, including patients both with normal and subnormal concentrations of FT4. From the above it appears that low stimulated concentrations of TSH in the presence of subnormal concentrations of FT4 indicate an extremely poor prognosis in critically ill patients. The abnormal behaviour of TSH in this group of patients cannot be explained by generalized pituitary insufficiency or by an increase in FT4.

Topics: Adult; Aged; Bacterial Infections; Female; Follicle Stimulating Hormone; Humans; Luteinizing Hormone; Male; Middle Aged; Pituitary Gland; Prolactin; Sepsis; Syndrome; Thyroglobulin; Thyroid Gland; Thyrotropin; Thyrotropin-Releasing Hormone; Thyroxine; Triiodothyronine; Triiodothyronine, Reverse; Virus Diseases

Thyroid function tests were obtained from 335 consecutive patients admitted to an intensive care unit. Twenty patients suffering from severe non-endocrine diseases (septicaemia, fulminant hepatic and renal failure, acute pancreatitis, polytrauma, cerebral haemorrhage) were found to have serum thyroxine levels in the hypothyroid range (less than 4 micrograms/dl). Serum concentrations of total thyroxine (2.3 +/- 0.2 micrograms/dl), triiodothyronine (0.23 +/- 0.03 ng/ml), and thyroxine binding globulin (15.1 +/- 1.3 micrograms/ml) were reduced, but were above normal for reverse triiodothyronine (0.43 +/- 0.06 ng/ml). Response of TSH secretion to iv TRH was found to be either normal, lowered or absent. Primary hypothyroidism was excluded, as no enhanced TSH response was observed in any case. Although decreased thyroxine levels may be due to increased thyroid hormone degradation it appears that associated impaired TSH responsiveness to TRH may result from illness-related inhibition of pituitary TSH release. Although the finding of decreased thyroid hormone levels is not rare in care patients, it represents an index of poor prognosis. Differentiation between this "low-T4 syndrome" and true hypothyroidism depends essentially on clinical symptoms and course of disease.

Topics: Acute Disease; Acute Kidney Injury; Adolescent; Adult; Aged; Critical Care; Female; Hepatic Encephalopathy; Humans; Hypothyroidism; Male; Middle Aged; Pancreatitis; Pituitary Gland; Sepsis; Thyroid Function Tests; Thyroid Gland; Thyrotropin; Thyroxine; Thyroxine-Binding Proteins; Triiodothyronine; Triiodothyronine, Reverse; Wounds and Injuries

Depressed triiodothyronine and elevated reverse triiodothyronine levels are commonly seen in patients with acute and chronic illness and in patients receiving markedly hypocaloric diets. To investigate the role of nutritional adequacy in causing the altered thyroid hormone levels found in severe illness, we studied patients with bacterial sepsis who were receiving a variety of nutritional regimens. Thirteen patients received only 5% dextrose in water (600-1000 kcal/day), 7 of whom were in shock. Seven patients received total parenteral nutrition (2500-3500 kcal/day). Analysis of thyroid hormone levels in these groups and in controls shows that a large component of the alteration in thyroid hormone levels found in patients with severe illness is due to the caloric deprivation associated with such severe illness.

Topics: Acute Disease; Adult; Aged; Bacteria; Chronic Disease; Female; Humans; Male; Middle Aged; Nutritional Physiological Phenomena; Sepsis; Thyrotropin; Thyroxine; Triiodothyronine; Triiodothyronine, Reverse