Thyroid illnesses

Surks, M. I., Hupart, K. H., Pan, C., and Shapiro, L. E., Normal free thyroxine in critical non-thyroidal illnesses measured by ultrafiltration of undiluted serum and equilibrium dialysis. J. Clin. Endocrinol. Metab. 67, 1031-1039 (1988). 

Since thyroid illness is commonly associated with depression, especially in women, it has long been observed that treating the thyroid abnormalities also can reverse the depression. This is especially true for treating hypothyroidism with thyroid hormone replacement (either T3 or T4). It has even been observed that giving supplemental thyroid hormone to depressed patients unresponsive to first-line antidepressants but without overt hypothyroidism can boost the antidepressant response of the first-line antidepressant (thyroid combo in Fig. 7—30). Thyroid hormone is also commonly administered to bipolar patients resistant to mood stabilizers, particularly those with rapid cycling (see discussion of combinations for bipolar disorders below). 

Oppenheimer, J. H., Squef, R., Surks, M. I., and Hauer, H., Binding of thyroxine by serum proteins evaluated by equilibrium dialysis and electrophoretic techniques Alterations in non-thyroidal illness. J. Clin. Invest. 42, 1769-1782 (1963). 

The interjiretalion of TSH. T and T, results may not be straightforward in the elderly population as these patients usually have more than one active disease process. A patient with a severe non-thyroidal illness may show low Tj, T, and TSH (p. 8.1). A patient s thyroid function can only be satisfactorily investigated in the absence of non-thyroidal illness. Elderly patients may also be taking drugs which affect thyroid function (Table 2). 

These changes result in sick patients having low serum Tj. T, and T.SH, and if thyroid function tests are requested the results may well be misinterpreted. A typical non-thyroidal illness pattern might be ... 

These results were obtained in a man with acute pancreatitis. In developing hypothyroidism the T, would be maintained within the reference range. In decreased TBG stales the T4 and T3 would fall in parallel. A low T, is almo.st invariably due to the presence of non-thyroidal illness. 

Patients with severe non-thyroidal illness may show apparent abnormalities in thyroid hormone resuits, known as the low T3 syndrome or non-thyroidal illness pattern of results. 

Mooney, C. T., R. E. Shiel, and R. M. Dixon. 2008. Thyroid hormone abnormalities and outcome in dogs with non-thyroidal illness. Journal of Small Animal Practice 49 11-16. 

Daily urinary excretion of iodide and most suitable indices of iodide excretion in children 24 hour collected urine together with first and second voiding urine specimen were collected from 55 non-thyroidal ill patients aged 5 to 21. Daily iodide excretion expressed as u mol/M /day was compared with 24-hour urine, first and second voiding urine iodide creatine ratio(umol/g Cr). 

Presently, circulating T3, T4, and TSH are an adequate basis to assess the thyroid status. Because, T4 is highly boimd to proteins in serum (mainly TBG) it is necessary to consider the measurement of the free fraction of the hormone. In developed countries with a normal iodine intake most of the FT4 techniques perform similarly with the exception of particular situations (pregnant women, non-thyroidal illnesses). But, when iodine deficiency coexisted with nutritional problems, we experienced serious difficulties with most of the commercial assays. In our hands, the FT4 index calculated as the ratio of T4 to TBG is the most appropriate tool. 

M. Bonnyns, P. Bourdoux, Thyroid function and non-thyroidal illness prevalence of thyroid biochemical abnormalities, Eur J Intern Med 1 213 (1990). 

Sizemore, G. W. Heath, H. Ill "Immunochemical Heterogeneity of Calcitonin in Plasma of Patients With Medullary Carcinoma of the Thyroid". J. Clin. Invest. (1975), In Press. 

Langton JE, Brent GA. Nonthyroidal illness syndrome Evaluation of thyroid function in sick patients. Endocrinol Metab Clin North Am 2002 31 159-172. 

C16. Chopra, I. J., Sakane, S., and Chua Teco, G. N., A study of the serum concentration of tumor necrosis factor-a in thyroidal and nonthyroidal illness. J. Clin. Endocrinol. Metab. 12, 1113-1116(1991). 

W18. Wong, T. K., and Hershman, J. M., Changes in thyroid function in nonthyroid illness. Trends Endocrinol. Metab. 3, 8-12 (1992). 

The adult brain is endowed with nuclear as well as cytosolic and membrane T3 receptors that have been visualized by autoradiography and studied biochemically [30-33]. Both neurons and neuropil are labeled by [ 1251]T3, and the labeling is selective across brain regions. Functionally, one of the most prominent features of neural action of thyroid hormone in adulthood is subsensitivity to norepinephrine as a result of a hypothyroid state [27], These changes may be reflections of loss of dendritic spines in at least some neurons of the adultbrain. Clinically, thyroid hormone deficiency increases the probability of depressive illness, whereas thyroid excess increases the probability of mania (Ch. 52) in susceptible individuals [27],... 

Thyroid hormone production is regulated by TSH secreted by the anterior pituitary, which in turn is under negative feedback control by the circulating level of free thyroid hormone and the positive influence of hypothalamic thyrotropin-releasing hormone. Thyroid hormone production is also regulated by extrathyroidal deiodination of T4 to T3, which can be affected by nutrition, nonthyroidal hormones, drugs, and illness. 

Primary osteoporosis is the most common form of the condition. The secondary form of osteoporosis is diagnosed when an illness and/or medications are present with a negative impact on BMD. Examples of common chronic conditions in old people that can cause secondary osteoporosis are seen in Box 5.14. Examples of drugs that can cause secondary osteoporosis are glucocorticoids, too high doses of thyroid hormone, anticonvulsants, and heparin. Especially the use of glucocorticoids has been known to cause severe osteoporosis even within a short period of treatment. Depending on the doses the development of osteoporosis can occur within a few weeks or months. 

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