Enlarged Thyroid Gland
Enlarged thyroid, also known as goiter, can result from diseases of the thyroid gland and number of other causes.
What is Thyroid Gland?
Thyroid gland is one of the endocrine glands and it is located in the front part of the neck, below Adam’s apple. It is a butterfly-shaped gland that produces hormones that regulate metabolism, growth, sexual development and other vital functions of the body. Two main hormones secreted by the thyroid gland include thyroxine (T4) and triiodothyronine (T3) and their secretion is regulated by thyroid stimulating hormone (TSH), which is produced by the pituitary gland. Abnormal production of thyroid stimulating hormone can cause thyroid to become enlarged. Enlargement of the thyroid can be easily noticed and it may appear as swollen lump in the neck.
Causes of Enlarged Thyroid
A diet deficient in iodine can cause enlargement of the thyroid because iodine is essential for secretion of thyroid hormones. Deficiency of iodine leads to over stimulation of the thyroid gland thus enlarged thyroid. However, iodine deficiency is rarely the cause for enlarged thyroid in developed countries because iodine is routinely added to table salt. More commonly, enlarged thyroid gland results from certain thyroid diseases. Grave’s disease is an autoimmune disorder characterized by excess production of thyroid hormones. It is caused by antibodies produced by the immune system that attack thyroid gland and lead to enlargement of the gland. Hashimoto’s disease can lead to goiter as well. It is also an autoimmune disease that affects thyroid gland causing it produce too little thyroid hormones. Due to low thyroid hormone levels, the pituitary gland produces more TSH to stimulate thyroid, which consequently leads to goiter. Thyroid nodules can cause enlarged thyroid too. In this disorder, one or more nodules filled with fluid develop on the thyroid gland. These nodules are normally benign and rarely develop into cancer. Thyroiditis is an inflammation of the thyroid gland which often leads to enlarged thyroid gland. Thyroiditis can be caused by bacterial infection and other factors. Another cause of enlarged thyroid can be thyroid cancer but it causes the gland to enlarge on one side only.
Symptoms of Enlarged Thyroid
Common symptoms of enlarged thyroid include: visible swelling at the base of the neck, neck pain, difficulty swallowing, difficulty breathing, coughing, and hoarseness.
Not all affected individuals experience the same symptoms but swelling is usually present. If enlarged thyroid is caused by hypothyroidism, the symptoms may also include: excessive tiredness, dry and itchy skin, weight gain and constipation. If hyperthyroidism causes goiter, the symptoms are: increased appetite, weight loss, anxiety, tremor and rapid heartbeat.
Treatment for Enlarged Thyroid
Enlarged thyroid is treated depending on the cause, symptoms and the size of the goiter. Treatment can include medications like thyroid hormone replacement to normalize hormone levels or corticosteroids to reduce the inflammation of the thyroid. Surgery to remove the goiter is performed in case of the cancer or nodules. Radioactive iodine can be used to treat overactive thyroid and reduce the size of the goiter though it may sometimes cause hypothyroidism.