Of hypothyroidism

Thyroid-stimulating hormone can be used clinically to test thyroid function but has not found practical apphcation in the treatment of human thyroid insufficiency. Direct replacement therapy with thyroid hormone is easy and effective, owing to a simple molecular stmcture. TSH has been used in the veterinary treatment of hypothyroidism, and preparations of TSH ate produced by Cooper Animal Health, Inc. and Armour Pharmaceuticals. 

Lithium. In the lithium carbonate treatment of certain psychotic states, a low incidence (3.6%) of hypothyroidism and goiter production have been observed as side effects (6,36) (see Psychopharmacologicalagents). It has been proposed that the mechanism of this action is the inhibition of adenyl cyclase. Lithium salts have not found general acceptance in the treatment of hyperthyroidism (see Lithiumand lithium compounds). 

Decreased activity of the thyroid gland results in hypothyroidism and, in severe cases, myxoedema. It is often of immunological origin and the manifestations are low metabolic rate, slow speech, lethargy, bradycardia, increased sensitivity to cold, and mental impairment. Myxoedema includes a characteristic thickening of the skin. Therapy of thyroid tumours is another cause of hypothyroidism. Thyroid deficiency... 

The symptoms of hypothyroidism and hyperthyroidism are given in Table 51-1. A severe form of hyperthyroidism, called thyrotoxicosis or tiiyroid storm, is characterized by high fever, extreme tachycardia, and altered mental status. Thyroid hormones are used to treat hypothyroidism and antithyroid... 

After a patient receives a diagnosis of hypothyroidism and before therapy starts, the nurse takes vital signs and weighs the patient. A history of the patient s signs and symptoms is obtained. The nurse performs a general physical assessment to determine outward signs of hypothyroidism. 

The symptoms of hypothyroidism maybe confused with symptoms associated with aging, such as depression, cold intolerance, weight gain, confusion, or unsteady gait. The presence of these symptoms should be thoroughly evaluated and documented in the preadministration assessment and periodically throughout therapy. 

IVday, monitor urinalysis, osmolality, and specific gravity every 3 months. Thyroid function tests should be obtained once or twice during the first 6 months, then every 6-12 months monitor for signs and symptoms of hypothyroidism if supplemental thyroid therapy is required, monitor thyroid function tests and adjust thyroid dose every 1-2 months until thyroid function indices are within normal range, then monitor every 3-6 months. 

Identify the typical signs and symptoms of hypothyroidism and the consequences of inadequate treatment. 

Describe the clinical use of levothyroxine in the treatment of hypothyroidism, including initial dose and dose titration, and patient monitoring. 

Describe the management of hypothyroidism and hyperthyroidism in pregnant women. 

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). 

There are three major goals in the treatment of hypothyroidism replace the missing hormones, relieve symptoms, and achieve a stable biochemical euthyroid state. 

The most common causes of hypothyroidism are listed in Table 41-2. Up to 90% of patients with autoimmune thyroiditis have circulating anti-TPOAbs. The autoimmune inflammatory response results in a lymphocytic infiltration of the thyroid gland and its eventual destruction. 

Liothyronine (Cytomel ) SyntheticT3 5, 25, and 50 meg tablets 15 meg Rarely needed in treatment of hypothyroidism rapid absorption and pharmacologic effect increased toxicity versus LT4 no outcome benefit to combining with LT4... 

Patients who receive radioactive iodine must be monitored for the development of hypothyroidism. 

Complications of surgery include persistent or recurrent hyperthyroidism (0.6% to 18%), hypothyroidism (up to about 49%), hypoparathyroidism (up to 4%), and vocal cord abnormalities (up to 5%). The frequent occurrence of hypothyroidism requires periodic follow-up for identification and treatment. 

Clinical signs of continuing thyrotoxicosis or the development of hypothyroidism should be noted. 

The vast majority of hypothyroid patients have thyroid gland failure (primary hypothyroidism). The causes include chronic autoimmune thyroiditis (Hashimoto s disease), iatrogenic hypothyroidism, iodine deficiency, enzyme defects, thyroid hypoplasia, and goitrogens. 

Myxedema coma is a rare consequence of decompensated hypothyroidism manifested by hypothermia, advanced stages of hypothyroid symptoms, and altered sensorium ranging from delirium to coma. Untreated disease is associated with a high mortality rate. 

A rise in the TSH level is the first evidence of primary hypothyroidism. Many patients have a free T4 level within the normal range (compensated hypothyroidism) and few, if any, symptoms of hypothyroidism. As the disease progresses, the free T4 concentration drops below the normal level. The T3 concentration is often maintained in the normal range despite a low T4. Antithyroid peroxidase antibodies and antithyroglobulin antibodies are likely to be elevated. The RAIU is not a useful test in the evaluation of hypothyroidism because it can be low, normal, or even elevated. 

The treatment goals for hypothyroidism are to normalize thyroid hormone concentrations in tissue, provide symptomatic relief, prevent neurologic deficits in newborns and children, and reverse the biochemical abnormalities of hypothyroidism. 

BrtVHaWBa Thyroid Preparations Used in the Treatment of Hypothyroidism ... 

During treatment of hyperthyroidism, Lp(a), as well as LDL cholesterol and apolipoprotein B, increases, indicating an effect of thyroid hormone on receptor activity and on protein synthesis. The opposite effect is observed in treatment of hypothyroidism (B27, E9, K16). 

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