subclinical hyperthyroidism

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Related to subclinical hyperthyroidism: subclinical hypothyroidism

subclinical hyperthyroidism

A low serum TSH concentration in an asymptomatic person with normal serum thyroid hormone concentrations; SH is more common in older–> age 60 Pts, and detected by measuring TSH Etiology Solitary thyroid adenoma, multinodular goiter, subclinical Graves' disease Clinical A Fib, atrial premature contractions, ↑ pulse rate, ↑ left ventricular mass and contractility, osteoporosis Management Treatment may be unnecessary
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


(hi?per-thi'royd-izm) [? + thyreos, shield, + eidos, form, shape, + -ismos, state of]
A disease caused by excessive levels of thyroid hormone in the body.


The condition may result from various disorders such as nodular goiter and toxic adenomas, hyperemesis gravidarum, excessive thyroid hormone replacement, excessive iodine ingestion, or pituitary adenoma; however, the most common cause is Graves' disease. Synonym: thyrotoxicosis See: Graves' disease


In general, the signs and symptoms of hyperthyroidism are divided into two categories—those secondary to excessive stimulation of the sympathetic nervous system and those due to excessive levels of circulating thyroxine (T4). The symptoms caused by sympathetic (adrenergic) stimulation include tachycardia, tremor, increased systolic blood pressure, hyperreflexia, eyelid lag (lagophthalmos), staring, palpitations, depression, nervousness, and anxiety. Symptoms caused by increased circulating thyroxine include increased metabolism, hyperphagia, weight loss, and some psychological disturbances. In elderly persons, symptoms of hyperthyroidism are often blunted. See: apathetic hyperthyroidism


Definitive therapies include surgical removal of the thyroid gland, radioactive iodine ablation of the gland, or antithyroid drugs. The choice of treatment is individualized for each patient, depending on the size of the goiter, the cause, patient’s age, and parity.

Patient care

Vital signs, fluid balance, and weight are monitored, and activity patterns are documented. Serum electrolyte levels are monitored, blood glucose levels are checked for evidence of hyperglycemia and urine for glycosuria, and the ECG is evaluated for arrhythmias and ST-segment changes. The patient is assessed for classic signs and symptoms (as above) and for indications of thyrotoxic crisis or heart failure. The patient's knowledge of the disorder is determined, misconceptions are corrected, and information on the condition, related problems, and symptom management is provided. Medical treatments, including radioactive iodine, are administered and evaluated for desired response and adverse reactions, and the patient is instructed about these treatments (esp. regarding 131I precautions). If the patient has exophthalmos, isotonic eyedrops are instilled to moisten the conjunctivae, and sunglasses or eye patches are recommended to protect the eyes from light. A high-caloric, high-vitamin, high-mineral diet, including between-meal snacks and avoidance of caffeinated beverages, is encouraged. Frequency and characteristics of the patient's stools are checked, and related skin care is provided as needed. The patient should minimize physical and emotional stress, balance rest and activity periods, and wear loose-fitting cotton clothing. A cool, dim, quiet environment also is recommended. The patient is prepared physically and emotionally for surgery if needed. Both patient and family are reassured that mood swings and nervousness will subside with treatment. The patient is encouraged to verbalize feelings about changes in body image. Assistance is provided to help the patient to identify and develop positive coping strategies. Emotional support is offered, and referral for further counseling is arranged as necessary. Life-long thyroid hormone replacement therapy will be necessary after surgical removal or radioactive iodine ablation treatment. The patient should wear or carry a medical identification device describing the condition and treatment and carry medication with him or her at all times.

apathetic hyperthyroidism

Overactivity of the thyroid gland, presenting as heart failure, arrhythmias (such as atrial fibrillation), weight loss, or psychological withdrawal. This is more often a presentation of hyperthyroidism in older than in younger patients. Diagnosis is usually easier in the latter group because they present with the classic symptoms of hyperthyroidism. Synonym: subclinical h

subclinical hyperthyroidism

Apathetic hyperthyroidism.
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
Out of 75 participants, 25 patients were subclinical hypothyroidism, 25 were subclinical hyperthyroidism, 25 were healthy control and the age ranged between 30 and 60 years.
Consistent with the literature, among 84 patients, only 1 (1.2%) case of subclinical hyperthyroidism was found.
Subclinical hyperthyroidism is a risk factor for poor functional outcome after ischemic stroke.
(2000) Endogenous subclinical hyperthyroidism affects quality of life and cardiac morphology and function young and middle-aged patients.
After adjusting for age, sex, and other fracture risk factors, the researchers found that individuals with subclinical hyperthyroidism had a 28% increase in the risk of any fracture and a 36% increased risk of hip fracture compared to individuals with normal thyroid function.
The relationship between overt and subclinical hyperthyroidism and proximal skeletal muscle strength has been investigated previously [2,4,9]; however, effects of hyperthyroidism on distal muscles of the upper limb have not yet been demonstrated.
On the contrary, these results imply that soy diet could be beneficial to subclinical hyperthyroidism, which is observed in about 8% of individuals of older than 65 years (Gesing et al.
Increased frequency of transient subclinical hyperthyroidism (normal FT3 and FT4 levels and TSH values below the normal range) has been reported early after allo-HSCT (peak incidence, about 100 days), mainly within the period of immunologic reconstitution suggesting that the major pathogenetic factor of thyroid damage is the immune system derangement occurring within the first 6 months after transplant [26, 88, 90].
Among the subjects who participated in this study, 3119 male, 22 female) had hyperthyroidism, 30 12 male, 28 female)--hypothyroidism, 31 15 male, 26)-- subclinical hyperthyroidism and 34 15 male, 29 female) had subclinical hypothyroidism.
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