Hyperthyroidism
In healthy people, the thyroid gland produces precise quantities of two hormones, T4 and T3, which have an effect on every aspect of the body's functioning. Research has shown that these hormones control many aspects of our metabolism which, in the final analysis, determines the number of calories a person expends, how warm he feels, and what is his weight. In other words, we can say that the thyroid "runs" our metabolism.
Hyperthyroidism
These hormones directly affect most organs, including the heart, which beats faster and harder under the influence of thyroid hormones. All the cells in the body will respond to an increase in the quantity of thyroid hormone by increasing the rate of their working. Hyperthyroidism or thyrotoxicosis is a clinical condition which results from over secretion of thyroidal hormones. It can be due to over-activity of the gland or as a result of localized over-activity due to single hyper-plastic nodule.
The following conditions are attributed to hyperthyroidism:
- Grave's Disease
- Congenital Thyrotoxicosis
- Transient Hyperthyroidism
- Metastatic Thyroid Carcinoma
According to the British Medical Journal and the British Thyroid Foundation, Graves Disease is caused mainly by the over-activity of the thyroid gland. It is the most common cause of hyperthyroidism and together with nodular goiter, it accounts for 99% of the cases. The causes of Grave's Disease are TSH producing tumors or increased production of TSH by a pituitary tumor [1]. Grave's Disease is more common in women than in men and occurs between the ages of puberty and menopause and, very rarely, in children. It is recognized as the consequence of a special type of thyroidal antibody. It may develop as the result of an emotional disturbance.
According to the Mayo Clinic, which has many years of experience with this condition, the patient complains of shortness of breath, tiredness, palpitations, nervousness, anxiety, muscular weakness, tremors of the hands, thyroidal enlargement and protruding eyeballs, intolerance of heat, increased appetite despite weight loss and odema of the ankles. The patient is tense, talkative and restless, has a rapid pulse that does not slow during sleep. Less common features of Grave's Disease are clubbing of the fingers.
Congenital Thyrotoxicosis According to the National Institute of Health, before birth, hyperthyroidism in the fetus may be suspected if the fetal heart rate is unduly rapid and if the mother has been treated in the past for hyperthyroidism. At birth the baby is emaciated and hyper-kinetic and may have goiter and diarrhea. The disease is self-limiting because of the half-life of the maternal IgG (Immunoglobin G) transferred across the placenta. Unless the thyroidal over-activity is controlled within the first two months of life, the infant may die.
Transient Hyperthyroidism This condition may occur in the early stages of Hashimoto's Thyroiditis.
References
1. Kendall-Taylor, P. (1975) The Aetiology of Thyrotoxicosis, Brit. J. Hosp. Med. 13, 640
