Abnormal enlargement of thyroid gland is termed as thyromegaly. Generally it is termed as goitre. The thyroid gland is located at the base of the neck and so very much visualized.
The function of thyroid gland is to produce thyroid hormone in presence of iodine. The production rate of thyroid hormone is very delicate, as under production (hypothyroidism) and even over production (hyperthyroidism) causes thyromegaly.
Image 1: Causes of Thyromegaly
In some cases it has been also observed that non cancerous growth of the cyst at the base of the breast bone which is filled with fluid or solid looks very similar like goitre is termed as euthyroid goitre.
The symptoms vary from individual to individuals, as the size of enlargement of the thyroid glands differ. Some common symptoms associated with thyromegaly are as follows:
- Noticeable swelling at the base of the neck
- Pain in neck
- Feeling of stiffness inside the neck during coughing
- Voice hoarseness
- Difficulty in breathing
- Intolerance of high temperature
- Difficulty in swallowing food
- Wight loss
- Problem in specking
- Bad breathing smell
- Fever is associated, if infection is developed in thyroid gland
Two types of thyroid hormones are produced in thyroid glands; they are thyroxine(T4) and tri-iodothyronine (T3). Excess production or minimal production of these two hormones can hamper the metabolism of carbohydrates and fats and results to imbalance of homeostasis which alters body temperature, heart rate and protein production.
Another important hormone is calcitonin which is also produced in thyroid gland. This calcitonin hormone maintains the blood calcium level. Thyroid glands activity is controlled by thyroid stimulating hormone (TSH) which is secreted by pituitary glands situated at the hypothalamus in the brain.
The following factors affect the thyroid gland enlargement:
Low Iodine consumption
Iodine is important component of thyroid hormone synthesis as T4 contains four iodine ions in their structure and T3 contains three iodine ions. Lack of iodine affects the molecular structure of the T4 and T3. The deficiency of the production of the hormone leads to hypothyroidism and which leads to thyroid gland enlargement.
Graves’ disease is the result of over production of thyroid hormones which occur due to autoimmunity. Malfunctioning of immune system stimulates thyroid gland more than the normal which synthesize more thyroid hormone than the normal amount and ultimately resultant is enlargement of thyroid gland.
This is also an autoimmune disease which destroys the tissues of thyroid gland and leads to under production of thyroid hormones. This condition is opposite of Graves’ disease. Hypothyroidism leads to swelling of the thyroid gland.
Multiple Nodules Development
Thyroid gland looks like a butterfly. Development of nodules in the thyroid gland often extended both the side of the gland causes enlargement.
- Thyroid gland cancer
Initial detection of underlying cause is important to treat thyromegaly. The initial monitoring is based on physical examination and thorough knowledge of patient’s medical history. Depending upon these factors doctors often suggest the diagnosis workout. The initial workout is based on blood test which is mainly performed to detect:
- T3, T4 and TSH level.
Other than blood tests, other diagnostic tools are:
- Ultra sounds
- CT Scan
The treatment is given for the reduction of enlargement of the thyroid gland which is possible by limiting the underlying cause. As enlargement may occur due to hypothyroidism or hyperthyroidism, then accordingly detection and treatment is related. In case of hypothyroidism the possible treatments are:
- Iodine rich food which can be supplemented with sea foods which are rich source of iodine.
- In pharmacy stores, thyroid hormone replacement pills are available which often doctors prescribed as first line therapy in case of hypothyroidism. Synthroid, Levothroid (levothyroxine), these two drugs are often prescribed and must be taken at empty stomach and can be continued as a lifelong therapy.
- Avoiding the foods and medicines that may exacerbate the condition.
In case of hyperthyroidism doctors often prescribe:
- Propylthiouracil and methimazole, these two drugs are often prescribed before giving the radioactive iodine therapy.
- Methimazole and propylthioracil are drugs which control hyperthyroidism by inhibiting the incorporation of iodine ion into the structure of T3 and T4.
- Propylthioracil is another medicine which limits the conversion from T4 to T3.
- Levethyroxine suppressive therapy is a long term treatment process, but it provides effective result in case of non-malignant hyperthyroidism.
Image 2: Thyroid Gland Surgery
Surgery is mainly recommended in case of malignancy or tumor development in the thyroid gland and cannot be effectively treated with radioactive iodine therapy or in case patient is not responding with other available treatments. Cosmetic surgery is rarely recommended in case of thyromegaly.