The thyroid gland is responsible for producing the thyroid hormone, which is a very important hormone that helps regulate body temperature, appetite and other metabolic functions. Low thyroid hormone levels lead to a condition known as hypothyroidism. In conditions that cause low levels of the thyroid hormone, the patient suffers from a metabolic imbalance. These diseases cause specific symptoms that can be used to diagnose the condition. Understanding which diseases cause hypothyroidism will aid physicians in treating their patients.
Hashimoto's Thyroiditis
Low thyroid levels can be caused by Hashimoto's thyroiditis, which is an autoimmune disorder, according to TeensHealth.org. Hashimoto's thyroiditis is the most common cause of hypothyroidism in teenagers. The patient's immune system attacks the cells and tissues in the thyroid that are responsible for producing the hormone. The thyroid attempts to compensate for this production by proliferating and producing more hormones. During this phase of compensation, the patient may develop a goiter, or a large mass in the center of the throat. However, as the disease progresses, the thyroid is unable to produce enough hormone to meet the body's needs.
Congenital Diseases
Some babies are born with a congenital defect in their thyroid glands. This makes the thyroid defective and unable to produce the thyroid hormone. An estimated one in 3,000 children are born with a defective or absent thyroid, reports MayoClinic.com. These babies most probably inherited this genetic defect from their parents. Babies may appear normal at birth, but quickly deteriorate if they do not receive hormone replacement therapy. Most states require newborns to be screened for thyroid function.
Subacute Thyroiditis
Subacute thyroiditis is a very confusing temporary disorder that affects the thyroid gland. When this condition occurs, it first produces a hyperthyroid state, then a hypothyroid state, and finally manifests a return to normal thyroid levels, states the New York Times Health Guide. Patients may exhibit signs of both hyperthyroidism and hypothyroidism. The symptoms typically last six to eight weeks. Subacute thyroiditis is responsible for 10 percent of all cases of hypothyroidism.
Pituitary Disorder
Thyroid stimulating hormone, or TSH, is a hormone produced in the pituitary gland that is responsible for regulating the production of thyroid hormone by the thyroid gland. In patients with a pituitary disorder, which decreases the levels of TSH, the level of thyroid hormone may drop drastically. Without TSH, a normally functioning thyroid gland will not produce any thyroid hormone. The most common pituitary disorder that leads to hypothyroidism is a benign tumor of the pituitary gland.
