Thyroid-stimulating hormone serum

Discuss the relationship between serum thyroid-stimulating hormone (TSH) levels and primary thyroid disease and the advantages for the use of TSH levels over other tests such as serum T4 (thyroxine) and T3 (triiodothyroinine) levels. 

O In most patients with thyroid hormone disorders, the measurement of a serum thyroid-stimulating hormone (TSH) level is adequate for the diagnosis of hypothyroidism and hyperthyroidism. The target TSH for most patients being treated for thyroid disorders should be the mean normal value of 1.4 milliunits/L or 1.4 microunits/mL (target range 0.5-2.5 milliunits/L or 0.5-2.5 microunits/mL). 

Thyroid Hormone (Thyroxine, Synthroid). The most common use of thyroxine in bipolar patients is the treatment of lithium-induced hypothyroidism. Approximately 5% of patients receiving long-term lithium treatment ultimately develop hypothyroidism. When this occurs, the patient with bipolar disorder may present with symptoms of a depressive episode. Therefore, periodic thyroid axis monitoring, that is, a serum thyroid stimulating hormone (TSH) test, is required for all patients taking lithium and should always be performed when the bipolar patient experiences a depressive episode. 

Parle JV, Franklyn JA, Cross KW, Jones SR, Sheppard MC. Thyroxine prescription in the community serum thyroid stimulating hormone level assays as an indicator of undertreatment or overtreatment. Br J Gen Pract 1993 43 107-9. 

It has been long recognized that prolonged lithium therapy can cause hypothyroidism. In fact, determination of serum thyroid-stimulating hormone once a year is recommended in all subjects on prolonged lithium therapy [32, 33]. Lithium perturbs receptor-mediated signaling events such as cyclic adenosine monophosphate and inositol phosphate accumulation [34]. These effects likely explain many hormonal side effects of lithium. 

Infertility in mares, particularly if they are obese, is sometimes ascribed to hypothyroidism (see Ch. 5). The role of hypothyroidism in equine fertility is unclear. Further research incorporating the evaluation of serum thyroid-stimulating hormone concentrations will help to further elucidate the role of thyroid hormones in equine infertility. 

The serum thyroid-stimulating hormone (TSH) is at a maximum between 0200 and 0400 and at a minimum between 1800 and 2200. The variation is of the order of 50%. There are also variations in the serum thyroxine concentration, but these appear to be related to the changes in concentration of binding protein brought about by changes in posture. These variations are maximal between 1000 and 1400. Total protein concentration may vary by as much as 10% over 24 hours, but the variation of individual proteins may be even greater. 

Hood, A., M. L. Allen, Y. Liu, J. Liu, and C. D. Klaassen. 2003. Induction of T(4) UDP-GT activity, serum thyroid stimulating hormone, and thyroid follicular cell proliferation in mice treated with microsomal enzyme inducers. Toxicology and Applied Pharmacology 188 6-13. 

Serum thyroid-stimulating hormone (TSH) and thyroid hormone levels should be measured in any patient with a goiter to determine the hormonal status. TSH concentrations increase with age, but the levels remain within the normal range in the healthy population throughout life up to 100 years of age (Canaris et al., 2000 Mariotti et al, 1995). See Chapter 106 by Diez and Iglesias on Hypothyroidism in the Middle Aged and Elderly Clinical Aspects for details of thyroid hormone changes in the elderly. Serum calcitonin levels are not needed unless there is a family history of medullary thyroid cancer or multiple endocrine neoplasia (MEN) type 2. 

The indicator for this condition is neonatal serum thyroid-stimulating hormone (TSH). A prevalence of 1-10% of elevated TSH has been reported from various endemic diseases (Kochupillai et ai, 1986). There is evidence from India of an epidemiological correlation, with subsequent intellectual performance from India (Kochupillai et ai, 1986) and elsewhere (Delange, 1994). 

Suboiinioai hypothyroidism is defined as a bioohemioal abnormality charaoterized by an elevated serum level of serum thyroid-stimulating hormone (TSH) with normal thyroid hormones and no clinical symptoms. 

Before ultrasound-guided fine-needle aspiration came into use, scintigraphy was believed to be the most important test for the evaluation of nodules in the thyroid gland. Scintigraphy should, however, still be used when the patient with a nodule has low serum thyroid-stimulating hormone (TSH) value, to confirm the diagnosis of a toxic adenoma. 

C21. Costom, B. H., Grumbach, M. M., and Kaplan, S. L., Effect of thyrotropinreleasing factor on serum thyroid-stimulating hormone. An approach to distinguishing hypothalamic from pituitary forms of idiopathic hypopituitary dwarfism. J, Clin. Invest. 50, 2219-2225 (1971). 

Fig. 7. Serum thyroid-stimulating hormone (TSH) response to thyrotropin-releasing hormone (TRH) in normal subjects and in patients with hyperthyroidism and primary hypothyroidism. Ordinate serum immunoreactive TSH ( iU/ml). S, Normal controls (n = 45) primary hypothyroidism (n " 26), serum TSH > 21 20 minutes after TRH E3, thyrotoxicosis (n = 35), serum TSH < 1.8...

Serum thyroid stimulating hormone (TSH) was measured by a modification of the double antibody technique.The normal range is 5 yoU/ml. 

The only other endocrine disrupting effect that has been evaluated related to antimony in the human population has been an analysis of urinary antimony levels in relation to certain serum thyroid hormones in the U.S. general population as assessed through the NHANES 2007-08 survey (Yorita Christensen 2012). There were no reported significant associations between concentrations of urinary antimony and levels of serum free and total T3 and T4 or with serum thyroid stimulating hormone (TSH). 

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