Hypothyroidism

What is Hypothyroidism?

Hypothyroidism is the medical condition where there is underproduction of thyroid hormone. Although the effects can be unpleasant or uncomfortable, most hypothyroid problems can be managed well if properly diagnosed and treated.

What are the causes of Hypothyroidism?

Most cases of hypothyroidism are due to the thyroid failing to produce enough hormone, the cause of which is not evident.'Hashimoto's thyroiditis' is an auto-immune disorder in which white blood cells gradually replace thyroid tissue, which is attacked by the immune-system (antibodies). This can result in hypothyroidism. When the thyroid gland has been surgically removed or chemically destroyed as treatment for hyperthyroidism, it can result in hypothyroidism. Exposure to excessive amounts of iodide can also cause hypothyroidism, especially if the person has had a history of thyroid problems. Hypothyroidism can be due to a pituitary disorder, or absence of the gland.

What are the symptoms of Hypothyroidism?

An infant with hypothyroidism is unusually inactive and quiet. Appetite may be poor and the baby sleeps for excessively long periods of time. Generally, hypothyroidism can result in lethargy, slower mental processes, reduced heart rate, increased sensitivity to cold and tingling or numbness in the hands, constipation, hoarseness of voice, weight gain and menstrual disturbance.

How do doctors diagnose Hypothyroidism?

Tests may be done to measure the level of hormones secreted by the thyroid itself and that of Thyroid Stimulating Hormone (TSH) secreted by the pituitary. TSH is the hormone that triggers the production of thyroid. The levels of this hormone in the blood are elevated when a person is hypothyroid. This is because the body attempts to increase the production of thyroid. The thyroid gland may have ‘hot’ or ‘cold’ nodules. If blood tests show elevated hormone levels, doctors may recommend other tests, including radioactive iodide uptake tests and scans to show what type of nodules are present. Hot nodules are those that actively trap iodide. They are rarely cancerous. But cold nodules showing low iodide concentrations, may indicate a possible malignancy. They may need further investigation. If a person is found to have a nodule in the thyroid gland, then periodic tests will have to be done.

What happens if Hypothyroidism is not treated?

If hypothyroidism is not treated for a long period of time, it can cause coma due to myxedema. This is a rare, but potentially fatal condition requiring immediate hormone injections. Lack of thyroid hormones in the body in neonates and infants can lead to cretinism (mental retardation) and dwarfism (stunted growth). That is why it is a dangerous condition when it occurs in this age group.

How is Hypothyroidism treated?

This condition requires long term treatment with hormones. Surgery and drugs cannot increase the production of thyroid hormone, once it has slowed down. Hormones from animal extracts are available, but doctors generally prescribe synthetic forms of thyroid hormone. Side effects are rare, but some people may experience nervousness or chest pain while taking this treatment. The levels of medication will have to be then adjusted to relieve unpleasant side-effects. Cancer of the thyroid may require surgical removal of the cancerous portion of the gland, or the entire gland itself. This is called thyroidectomy. If the cancer has spread beyond the thyroid, the other affected tissue, such as the lymph glands in the neck, will also have to be removed. Irradiation may also be necessary.