Virtual Medical Centre

Hypothyroidism

• What is Hypothyroidism?
• Who gets Hypothyroidism?
• Predisposing Factors
• Probable Outcomes
• How is Hypothyroidism Diagnosed?
• How is Hypothyroidism treated?
• Hypothyroidism References
• Drugs/Products Associated with Hypothyroidism

What is Hypothyroidism?

3D Animation on Thyroid Disease This animation brought to you by Blausen Medical Communications. Contact Andrew Walbank.

Hypothyroidism causes underactivity of the thyroid gland. It may be primary from disease of the thyroid gland or secondary to hypothalamic-pituitary axis.

Who gets Hypothyroidism?

• Spontaneous hypothyroidism is infrequent with a prevalence of 1-2% and occurs more commonly in women (8-10 times).
• Atrophic (autoimmune) hypothyroidism: six times more common in females.
• Incidence increases with age.
• Hashimoto's thyroiditis: more common in females and in late middle age.

Predisposing Factors

• Autoimmune disease (Hashimoto's thyroiditis): Autoimmune disorders occur when your immune system produces antibodies that attack your own tissues, as is the case in Hashimoto's thyroiditis. Sometimes this process occurs within the thyroid gland. It is still unclear as to why the body produces antibodies against its own tissues. A genetic flaw is a valid suggestion, but one that is yet to be proven
• Treatment with radioactive iodine: The most common treatment for people who produce too much thyroid hormone (hyperthyroidism) is radioactive iodine. Sadly on many occasions this form of treatment can have the effect of curing a person of their over active thyroid and leave them with an under active one.
• Radiation therapy: Radiation used to treat cancers of the head and neck can affect your thyroid gland and may lead to hypothyroidism.
• Thyroid surgery: Removing all or a large portion of your thyroid can diminish or halt it capability to produce hormones. Thyroid hormone treatment would then have to be taken for life.
• Medications: A number of medications can contribute to hypothyroidism. One of the most common is lithium, which is used to treat certain psychiatric disorders.

On rare occasions the following may lead to hypothyroidism:

• Congenital disease: Approximately one in 3,000 babies in the United States is born with a defective thyroid gland or no thyroid gland at all.
• Iodine deficiency: The trace mineral iodine ? found primarily in seafood, seaweed, plants grown in iodine-rich soil and iodized salt ? is essential for the production of thyroid hormones.
• Pregnancy: Some women develop hypothyroidism during or after pregnancy (postpartum hypothyroidism), often because they produce antibodies to their own thyroid gland. Left untreated, hypothyroidism increases the risk of miscarriage, premature delivery and preeclampsia- a condition that causes a significant rise in a woman's blood pressure during the last three months of pregnancy. It can also seriously affect the developing fetus.
• Pituitary disorders: About 1 percent of cases of hypothyroidism are caused by the failure of the pituitary gland to produce enough TSH - usually due to a benign tumor of the pituitary gland.