Endocrinology and Metabolism Clinics of North America
The Nonthyroidal Illness Syndrome
Section snippets
Alterations of thyroid economy with nonthyroidal illness
Thyroid hormone parameters in nonthyroidal illness have been reviewed in detail elsewhere [10]. We provide a brief summary of the changes typically observed.
Starvation and fasting
The fasting state causes a down-regulation in the hypothalamic-pituitary-thyroid axis and hence decreased thyroid hormone levels [14], [15]. It may be difficult to distinguish between the effects on thyroid function of a given systemic illness versus those of the associated absolute or relative starvation because malnutrition is a component of many acute and chronic diseases. The decreased serum T3 in starvation is hypothesized to reflect an attempt by the organism to conserve energy by
Effects of drugs on thyroid economy
Pharmacologic agents administered to patients who have systemic illness may confound the interpretation of thyroid function tests. A complete review of drug effects on the hypothalamic-pituitary-thyroid axis is beyond the scope of this article and has been reviewed previously [72], [73]. The following section highlights the alterations in thyroid function parameters secondary to drugs commonly used in severe systemic illness.
Thyroid hormone treatment during nonthyroidal illness
The commonly held notion that patients who have nonthyroidal illness are euthyroid continues to be debated [1], [5], [91], [92], [93], [94], [95], [96], [97]. The metabolic state in these patients has been deemed to be euthyroid based on generally normal TSH and free T4 measurements. Changes in thyroidal economy may play an adaptive role in times of stress, but consideration has also been given to the possibility that patients who have nonthyroidal illness and low thyroid hormone levels may not
Summary
The evaluation of altered thyroid function parameters in systemic illness and stress remains complex because changes occur at all levels of the hypothalamic-pituitary-thyroid axis. Nonthyroidal illness syndrome is generally characterized by low serum T3, normal free T4 and TSH, and elevated rT3 values. Unique changes in thyroid function parameters are observed in various clinical states, including starvation and fasting, cardiac disease, renal disease, hepatic disease, and infection. Many
References (111)
- et al.
Endocrine and metabolic dysfunction syndromes in the critically ill: thyroid function in the intensive care unit setting
Crit Care Clin
(2001) - et al.
The effect of T3 and reverse T3 administration on muscle protein catabolism during fasting as measured by 3-methylhistidine excretion
Metabolism
(1979) - et al.
Glucose modulation of alterations in serum iodothyronine concentrations induced by fasting
Metabolism
(1979) Effect of dietary composition on fasting-induced changes in serum thyroid hormones and thyrotropin
Metabolism
(1978)- et al.
Altered thyroid hormone levels in bacterial sepsis: the role of nutritional adequacy
Metabolism
(1980) The effects of disease and drugs on thyroid function tests
Med Clin North Am
(1991)- et al.
Indices of thyroid function and weight loss in human immunodeficiency virus infection and the acquired immunodeficiency syndrome
Metabolism
(1993) - et al.
Hypothyroid-like regulation of the pituitary thyroid axis in stable human immunodeficiency virus infection
Metabolism
(1993) - et al.
Endocrine disorders in men infected with human immunodeficiency virus
Am J Med
(1988) - et al.
Low triiodothyronine and survival in end-stage renal disease
Kidney Int
(2006)
Effect of long-term amiodarone therapy on thyroid hormone levels and thyroid function
Am J Med
Free thyroxine measured in undiluted serum by dialysis and ultrafiltration: effects of non-thyroidal illness and an acute load of salicylate of heparin
Clin Chim Acta
Effects of commonly prescribed nonsteroidal anti-inflammatory drugs on thyroid hormone measurements
Am J Med
Serum thyroxine, free T4, triiodothyronine and reverse-T3 in diphenylhydantoin-treated patients
Metabolism
The low T3 or “sick euthyroid syndrome”: update 1994
Endocr Rev
Measurement of free hormones in blood
Endocr Rev
Measurement of thyroxine uptake from serum by cultured human hepatocytes as an index of thyroid status: reduced thyroxine uptake from serum of patients with nonthyroidal illness
J Clin Endocrinol Metab
Dangerous dogmas in medicine: the nonthyroidal illness syndrome
J Clin Endocrinol Metab
Do thyroid function tests independently predict survival in the critically ill?
Thyroid
Alterations of mental status and thyroid hormones after thermal injury
J Clin Endocrinol Metab
Evaluation of the pituitary-thyroid axis response to acute myocardial infarction
J Clin Invest
Serum rT3 and T3/rT3 are prognostic markers in critically ill patients and are associated with post-mortem tissue deiodinase activities
J Clin Endocrinol Metab
Alterations in thyroid function in patients with systemic illness: the “euthyroid sick syndrome”
Endocr Rev
Thyroxine metabolism in the low thyroxine state of critical nonthyroidal illnesses
J Clin Endocrinol Metab
Simultaneous measurement of free thyroxine and free 3,5,3-triiodothyronine in undiluted serum by direct equilibrium dialysis/radioimmunoassay: evidence that free triiodothyronine and free thyroxine are normal in many patients with the low triiodothyronine syndrome
Thyroid
Reverse T3 does not reliably differentiate hypothyroid sick syndrome from euthyroid sick syndrome
Thyroid
The production and metabolism of 3,5,3-triiodothyronine and 3,3,5-triiodothyronine in normal and fasting subjects
J Clin Endocrinol Metab
Inhibition of hypothalamic thyrotropin-releasing hormone messenger ribonucleic acid during food deprivation
Endocrinology
Effect of triiodothyronine replacement n the metabolic and pituitary responses to starvation
N Engl J Med
Inhibition of thyroxine transport into cultured rat hepatocytes by serum of nonuremic critically ill patients: effects of bilirubin and non-esterified fatty acids
J Clin Endocrinol Metab
Decrease in serum free triiodothyronine, thyroxine-binding globulin and thyroxine-binding prealbumin whilst taking a very low-calorie diet
Int J Obes
Effect of long-term calorie restriction with adequate protein and micronutrients on thyroid hormones
J Clin Endocrinol Metab
Effect of TRH on TSH glycosylation and biological action
Ann NY Acad Sci
Nature of suppressed TSH secretion during undernutrition: effect of fasting and refeeding on TSH responses to prolonged TRH infusions
Metabolism
Role of leptin in the neuroendocrine response to fasting
Nature
Leptin, nutrition, and the thyroid: the why, the wherefore, and the wiring
J Clin Invest
The central melanocortin system affects the hypothalamo-pituitary thyroid axis and may mediate the effect of leptin
J Clin Invest
The role of falling leptin levels in the neuroendocrine and metabolic adaptation to short-term starvation in healthy men
J Clin Invest
The impact of nutrition on thyroid hormone physiology and action
Annu Rev Nutr
The impact of iron and selenium deficiencies on iodine and thyroid metabolism: biochemistry and relevance to public health
Thyroid
Activation of the hypothalamo-pituitary-adrenal axis in response to septic or non-septic disease: implications for the euthyroid sick syndrome
Intensive Care Med
A potential role of activated NF-kB in the pathogenesis of euthyroid sick syndrome
J Clin Invest
Neuroendocrine-immune interactions
N Engl J Med
Update on thyrotropin-releasing hormone
Thyroid Today
The role of endogenous cortisol in patients with non-thyroidal illness and decreased T3 levels
Acta Med Scand
Endocrine and metabolic disturbances in human immunodeficiency virus infection and the acquired immune deficiency syndrome
Endocr Rev
Unique alterations of thyroid hormone indices in the acquired immunodeficiency syndrome (AIDS)
Ann Intern Med
2006 Thyroid function in human immunodeficiency virus patients treated with highly active antiretroviral therapy (HAART): a longitudinal study
Clin Endocrinol (Oxf)
The thyroid and the heart
Circulation
Mechanisms of disease: thyroid hormone and the cardiovascular system
N Engl J Med
Cited by (171)
Thyroid hormones in persons with schizophrenia: A systematic review and meta-analysis
2021, Progress in Neuro-Psychopharmacology and Biological PsychiatryNew causes of hypophysitis
2019, Best Practice and Research: Clinical Endocrinology and MetabolismCitation Excerpt :Hence patients present with GH, prolactin and TSH deficiencies with detectable anti-Pit 1 antibodies [84]. The exact pathogenesis is unclear, and it is thought that the aberrant expression of Pit-1 in the thymoma might play a role in the development of this condition [85]. In patients with immune CPI-mediated and lymphocytic hypophysitis associated with pregnancy, the diagnosis may be established with relative confidence.
Thyroid hormone may predict treatment failure in Kawasaki disease
2024, Pediatrics InternationalCorrelation analysis of low triiodothyronine syndrome with severity and prognosis of anti-N-methyl-D-aspartate receptor encephalitis
2023, Academic Journal of Naval Medical University