A thyroid gland that is enlarged is called a goiter. There are a variety of reasons for a goiter to develop, and all the causes take time to enlarge the thyroid and turn it into a goiter. Goiter development falls into three categories:
- Hyperplastic – which happens either because the gland is working harder to make hormone and grows, or causes growth of the entire gland.
- Inflammatory – which is caused by the immune system either attacking the thyroid by mistake or causing inflammation and swelling in the thyroid.
- Nodular – caused by benign or cancerous tumors developing in the thyroid that causes growth of the thyroid. This can be due to a single nodule or multiple nodules (multinodular goiter). And the thyroid enlargement in these cases happens in the areas where the tumor/nodule is growing.
A goiter that is small and not pressing on the surrounding tissue is usually not a problem, unless the amount of hormones it produces is too low or excessive. Larger goiters can press on the breathing tube (trachea) or swallowing tube (esophagus), which may lead to shortness of breath, coughing or difficulty swallowing.
Often a goiter or nodule is identified when your physician feels your neck. Alternatively the may be seen when a neck scan is done looking for other issues and the thyroid abnormality is seen incidentally. To further work up a goiter to figure out the reason for it the following tests may be done:
- Thyroid hormone blood tests – checking the level of TSH, Free T3 & Free T4 will give you an indication wether the thyroid is working appropriately or is it over or under active.
- Thyroid antibody blood tests – if the thyroid is overactive then a blood test for TSI (Thyroid Stimulating Immunoglobulin) is done to see Grave’s Disease is present. If the thyroid is under active then TPO-Ab (Thyroid Peroxidase Antibody) test is done to see if Hashimoto’s Thyroiditis is present.
- Ultrasound – Will show the size and dimensions of the thyroid gland as well s the breathing tube. It will also show if there are any nodules in the thyroid, the size of it, and if the nodule has any suspicious features.