Hyperthyroidism – symptoms, causes, treatment
Hyperthyroidism is a very common syndrome, with multisystem manifestations (affects the cardiovascular, digestive, reproductive, nervous systems). This syndrome is induced by an excess secretion of thyroid hormones (thyroxine, triiodothyronine).
Causes of hyperthyroidism
Predisposing factors of this disease include gender (hyperthyroidism meets with predilection in women), age (hyperthyroidism interests all ages but is more frequently in adulthood), hereditary factors (expressed in Basedow’s disease), neuropsychological factors (repeated stress), toxic factors (administration of large doses of thyroid hormones in patients with normal thyroid function can lead to iatrogenic hyperthyroidism).
Hyperthyroidism (thyrotoxicosis) is a symptomatic complex which meets in the following conditions:
– Graves Basedow disease – is the most common form of hyperthyroidism;
– Toxic adenoma;
– Toxic multinodular goiter;
– Transient hyperthyroidism (subacute thyroiditis, Hashimoto thyroiditis);
– Iatrogenic hyperthyroidism – occurs in exogenous thyroid hormones poisoning;
– Differentiated thyroid carcinoma;
– Pituitary adenomas secreting thyreotrop hormone (this hormone regulates the secretion of thyroid hormones, thus elevated pituitary hormones will increase thyroid hormone secretion);
Clinically, hyperthyroidism has multisystem manifestations, as follows:
- musculoskeletal-skeletal system – is affected both skeletal system (generalized osteoporosis) and muscular system (muscle atrophy);
- cardiovascular – clinically appears sinus tachycardia (increased heart rate), atrial fibrillation, moderate hypertension and in advanced stages may occur heart failure;
- digestive system – intestinal transit is accelerated, the patient has several stools by day, but of normal consistency. It can be found an increased appetite, but with weight loss. In severe forms of disease may occur liver enlargement with liver damages and jaundice (yellowing of the skin and mucous membranes);
- reproductive function – is deficient in both sexes;
- nervous system – hyperthyroidism can be accompanied by a series of neurobehavioral disorders (anxiety, mental instability, impaired memory, inability to concentrate), motor nervous system disorders (tremor of the extremities which are permanent).
In addition to these systemic manifestations in Basedow-Graves disease appear a major clinical sign: ophthalmopathy (characterized by protrusion of eyeballs and is associated with lagophtalmy = abnormal shortening of eyelids, particularly of the upper eyelid that prevents full coverage of the eyeball, conjunctival edema and in more advanced stages the reduction or even loss of visual acuity).
Analysis in hyperthyroidism
Investigations necessary for the diagnosis of hyperthyroidism are of biochemical (glucose – increased, total proteins and albumin – are low, cholesterol and triglycerides – low, free fatty acids – raised, basal metabolism – greatly increased), hormones (thyroid hyperfunction is confirmed by thyroid hormones growth and pituitary hormone normally should be decreased to inhibit the secretion of thyroid hormones), imaging (thyroid ultrasound, CT – computer tomography or magnetic resonance imaging – MRI) and in vivo thyroid tests (the intake of iodine indices are greatly increased and scintigram). In Graves Basedow disease due to ophthalmopathy an ophthalmologist is required.
Complications of hyperthyroidism
Untreated hyperthyroidism leads to various cardiac complications (various arrhythmias that lead to congestive heart failure, especially in the elderly), muscle (muscle atrophy), bone (generalized osteoporosis), liver complications and thyreotoxic crisis which is the most severe complication of hyperthyroidism and clinically consists of extreme worsening of hyperthyroidism signs(vomiting, abdominal pain, jaundice, diarrhea, extreme agitation, hallucinations, delirium, confusion).
Treatment of hyperthyroidism
Treatment of hyperthyroidism may be:
– Drug therapy – applies in cases with recent onset – the usual therapy for Basedow disease includes: sedatives (phenobarbital), beta blockers (propranolol) and thyrostatic drugs (synthetic antithyroid drugs);
– Surgical treatment – consists of subtotal thyroidectomy (removal of a part of the thyroid) and applies in cases of Graves Basedow disease with large goiters and toxic adenoma;
– Iodine 131 – this form of therapy is indicated for patients over 40 years with recurrences after thyroidectomy and in those in which the intervention is contraindicated.