The thyroid gland is a butterfly-shaped endocrine gland that is located in the lower neck. It performs the function of secreting thyroid hormones called thyroxine (T4) and triiodothyronine (T3). These hormones that play a vital role in the regulation of blood pressure, body temperature, and heart rate. The pituitary gland produces thyroid stimulating hormone (TSH), which stimulates the production of thyroid hormones by the thyroid gland. Damage to the thyroid gland can manifest in the form of hypothyroidism (inadequate production of thyroid hormones) and hyperthyroidism (excessive production of thyroid hormones). When the gland becomes inflamed, one is diagnosed with thyroiditis. Thyroiditis is categorized into the following types: ➻ Hashimoto's thyroiditis ➻ Postpartum thyroiditis ➻ Subacute thyroiditis ➻ Silent thyroiditis ➻ Drug-induced thyroiditis ➻ Radiation-induced thyroiditis ➻ Acute infectious thyroiditis Hashimoto's thyroiditis occurs due to an abnormal immune response. It is an autoimmune disease wherein the immune system attacks the thyroid cells, mistaking them for foreign invaders. As the disease progresses, the levels of TSH increase, as the pituitary gland tries to induce the thyroid to make more hormone. However, the levels of T4 fall, as thyroid gland can't produce sufficient amounts of hormones. This gives rise to hypothyroidism. Postpartum thyroiditis is also believed to be caused by an abnormal immune response. The risk factors include preexisting autoimmune disease, family history of thyroiditis, and development of postpartum thyroiditis after a previous pregnancy. Subacute thyroiditis is attributed to an upper respiratory infection (mostly a viral infection). Silent thyroiditis mostly affects women who have just had a baby. It is believed that drugs such as interferon and amiodarone could be responsible for causing inflammation. Acute infectious thyroiditis is mostly caused by a bacterial infection. Hashimoto's thyroiditis is the most common thyroid disorder in US. It mostly affects women. People above the age of 40 years are more commonly affected. A list of risk factors for thyroiditis is given below: ➻ Family history or a personal history of thyroiditis and/or immune system disorder ➻ Pregnancy ➻ Infection (viral/bacterial) ➻ Radiation therapy ➻ Medications, like amiodarone or lithium The following table presents information on the causes and symptoms of different types of thyroiditis. It must now be clear that the symptoms differ according to the type of thyroiditis. These symptoms depend on the speed with which the thyroid gland is getting enlarged. Rapid destruction of thyroid cells causes symptoms similar to hyperthyroidism, which include: ➻ Sudden weight loss, even with a proper diet ➻ Rapid or irregular heartbeat ➻ Tremors ➻ Changes in bowel patterns; frequent bowel movements ➻ Brittle hair ➻ Increased sensitivity to heat ➻ Nervousness, anxiety, and irritability ➻ Fatigue ➻ Muscle weakness ➻ Goiter ➻ Difficulty sleeping ➻ Dry skin ➻ Menstrual irregularities If the thyroid gland is not producing sufficient amounts of hormones, it gives rise to hypothyroidism. The symptoms of hypothyroidism include: ➻ Fatigue ➻ Constipation ➻ Dry skin ➻ Thinning hair ➻ Slowed heart rate ➻ Depression ➻ Increased sensitivity to cold ➻ Unexplained weight gain ➻ Puffy face ➻ Muscle weakness ➻ High blood cholesterol levels ➻ Stiff muscles and joints ➻ Impaired memory ➻ Heavy and irregular menstrual periods Physical examination of the thyroid gland helps in determining if thyroid gland is enlarged. Blood tests (TSH, T4, and T3) give an account of the amount of thyroid hormones present in the blood. Thyroid scans can also be used to examine the thyroid gland. Biopsy of the gland can also help in identifying the cause. The treatment options can be ascertained only after identifying the type of the thyroiditis. For a patient affected by hyperthyroidism, the doctor may prescribe beta blockers to lower the increased heart rate. Such patients may also be given radioactive iodine, which shrinks the thyroid gland. Anti-thyroid medication also helps reduce the symptoms. In severe cases, surgical removal might be suggested. Hormone replacement therapy also helps restore the level of hormones, thereby regulating the metabolic activities. It prevents further inflammation of the thyroid gland. Analgesics might be recommended for patients affected by pain in the throat. In case of hypothyroidism, synthetic thyroid hormone (levothyroxine) is prescribed. If left untreated, thyroid disorders can result in permanent damage of the thyroid gland. Therefore, medical assistance must be immediately sought on experiencing the aforementioned symptoms. Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.