Thyroid Over active part 2

Causes
Hyperthyroidism is caused due to excess production of thyroid harmone. This excess production can be caused by various reasons like:
Graves’ disease
The highly common cause of hyperthyroidism is graves disease. This runs in families and usually occurs at all ages. However it is very common amongst women in age group between 40-20 years. In case you smoke, the possibilities to develop graves disease are very high. This is a autoimmune condition, which means the immune system accidentally attacks the healthy substance instead of toxic substance in your body. The reason for the immune to do so is still unknown.
Eyes can also be affected by grave’s disease, causing double vision and discomfort, known as graves ophalmopathy. The eyes also look prominent and ‘stand out’. It is believed that tissues around the eyes are affected by the antibodies in immune system.
Thyroid nodules
Lumps develop in thyroid glands, called as nodules. The reason for the lumps to develop is not known but they are non cancerous. These nodules contain thyroid tissue which is abnormal resulting in production of normal triiodothyronine or thyroxine resulting in hyperthyroidism. Abnormal thyroid tissues in nodules are toxic.
After graves disease the second most common hyperthyroidism disease is the toxic multinodular goitre. When more than two nodules are present in thyroid gland this occurs. In case a single nodule is present in thyroid gland it is called toxic thyroid nodule. Around 5% cases of hyperthyroidism are of toxic thyroid nodules.
Iodine
The iodine intake in food is absorbed by thyroid gland for production of thyroid hormones, triiodothyronine or thyroxine. Consuming supplements of iodine causes excess production of triiodothyronine or thyroine. When non toxic nodules are present in thyroid glands, this occurs.
Amiodarone
Amiodarone helps in controlling irregular heartbeats. This is also known as anti-arrhythmic. If non toxic nodules are present in thyroid glands consuming amiodarone causes hyperthyroidism as it contains iodine. This is called amiodarone-induced hyperthyroidism.
Follicular thyroid cancer
Cancer cells in thyroid glands produces triiodothyronine or thyroxine by itself resulting in follicular thyroid cancer.
Diagnosis
If you suspect having hyperthyroidism, you need to see the doctor. Diagnosis is largely based on symptoms and blood test results, which shows the functioning of thyroid gland. This test is called as thyroid function test.
Thyroid function test
In this test, analysis of blood is done in two ways to diagnose hyperthyroidism. A sample of blood is taken and testes are undertaken for thyroid stimulating hormone (TSH) and also levels of thyroid hormones, triiodothyronine or thyroxine. TSH is in pituitary gland of brain and also controls production of triiodothyronine and thyroxine. When levels of triiodothyronine and thyroxine in blood are normal, the pituitary glands stop releasing TSH, and when levels reduce, pituitary glands produces TSH to increase the levels. If Thyroid function test shows the levels of TSH in blood are low and consistent meaning you have hyperthyroidism. Low levels mean that thyroid gland is more active and making numerous thyroid hormones. Then levels of triiodothyronine and thyroxine need to be tested. In case you have hyperthyroidism, levels will be higher of both hormones, causing symptoms for hyperthyroidism.
Types of hyperthyroidism
Once hyperthyroidism is confirmed, you doctor can also tell whether its subclinical hyperthyroidism or overt hyperthyroidism. In case of overt hyperthyroidism, TSH levels are low and high are levels of triiodothyronine or thyroxine. The hyperthyroidism symptoms can be severe or moderate. In case of subclinical hyperthyroidism, TSH levels are low and normal levels of triiodothyronine or thyroxine. No symptoms are caused.