Hashimoto’s Thyroiditis: The Thyroid and Beyond

By: 
Jeffrey R. Garber, MD, FACP, FACE

Hashimoto’s thyroiditis, named after Japanese physician Dr. Haruko Hashimoto, who first described the illness in 1912, is the most common cause of hypothyroidism in the Western hemisphere and in most of the rest of the world. It is also the most common autoimmune disease known to man.

Hashimoto’s occurs when the body’s immune system attacks its own tissues, mistakenly sensing them as foreign. In the case of Hashimoto’s thyroiditis, thyroid gland tissue is attacked. The thyroid gland is part of the endocrine system and is responsible for releasing hormones into the bloodstream that regulate a wide range of vital body functions.

If your doctor suspects that you have Hashimoto’s because you have low thyroid hormone levels, a goiter (see below) or, in some cases, repeated miscarriages without explanation, you will most likely undergo blood tests looking for antibodies to the thyroid (anti-thyroglobulin, or Tg Ab, and anti-thyroid peroxidase, or anti-TPO Ab). These tests are positive in 95 percent of patients with Hashimoto’s thyroiditis. Therefore, it's unusual for there to be no antibodies in the blood of a Hashimoto’s patient. Once antibodies are determined to be present, they are diagnostic of Hashimoto’s thyroiditis and do not have to be monitored.

Hypothyroidism isn’t the only complication associated with Hashimoto’s thyroiditis. In some people, the condition can also cause a painless enlargement of the thyroid, commonly known as goiter. The larger the goiter, the more likely it is to be visible. A goiter, particularly a large one, may also cause symptoms such as difficulty swallowing. When this occurs you will have to undergo additional testing to determine if surgery is necessary to remove all or part of the goiter.

Hashimoto’s thyroiditis does not discriminate. It affects males and females as well as the young and the old. But it is most common in women, increases with age, and is more prevalent in those with a family history of thyroid disease or other autoimmune disease.

It is important to know that if you or a family member has any autoimmune disease the odds of developing the same or additional autoimmune disorders increase. Generally speaking, being predisposed to autoimmune conditions does not require screening for them. Nonetheless, it is important for you and your physicians to keep your family and personal history of autoimmune disease in mind when you have signs or symptoms that may be explained by one of these many diverse disorders.

Other autoimmune diseases that affect endocrine glands are:

Graves’ disease: It is the most common cause of hyperthyroidism in North America. Hyperthyroidism, or too much thyroid hormone, is the opposite of hypothyroidism, which Hashimoto’s thyroiditis often results in. Graves’ disease may be associated with thyroid eye disease which includes swollen, bulging, red eyes, widely open eyelids, and double vision. Treatment of the hyperthyroidism can be with drugs, surgery, or radioactive iodine (for more information, visit: http://thyroidawareness. com/sites/all/files/radioiodine-or-radioactive-iodine-therapy.pdf ). Mild eye problems can be treated with simple measures. If there are severe eye problems, a team specializing in thyroid eye disease is required.

Type 1 diabetes: Formerly known as Juvenile Onset Diabetes Mellitus, type 1 diabetes can affect people of any age and requires insulin treatment for survival.

Adrenal insufficiency (Addison’s disease): Addison’s disease occurs when the adrenal glands located on top of the kidneys don't produce adequate amounts of steroid hormones, which are required to combat medical stress and maintain body fluids. Steroid hormone therapy is required for survival.

Primary ovarian insufficiency or premature ovarian failure: The early onset of menopause, which causes infertility. Hypoparathyroidism: Parathyroid hormone is required to regulate calcium levels in the blood. It is produced by four small parathyroid glands located near the thyroid. Autoimmune hypoparathyroidism occurs when these glands are unable to produce enough parathyroid hormone. The condition is most commonly treated with calcium supplements and large doses of vitamin D. Synthetic parathyroid hormone has recently been approved as an additional therapy.

Hypophysitis: Inflammation of the pituitary gland, a gland located at the base of the brain which regulates thyroid, adrenal and gonadal (ovary and testicle) function and produces growth hormone necessary for growth in children. Treatment depends on which hormonal system has been affected.

Other categories and examples of autoimmune conditions, which are too numerous to cover in this article, include those affecting:

Blood
Pernicious Anemia: Vitamin B12 cannot be absorbed, leading to anemia and neurological disorders including nerve damage and, when severe, dementia. Treatment consists of B12 administration.

Gastrointestinal System
Celiac Disease: Sensitivity to gluten, which when eaten leads to inadequate absorption of other nutrients. Gluten is present in wheat, barley, rye, and oats. It can lead to erratic absorption of thyroid hormone, vitamin D, and iron, causing low thyroid hormone levels, bone loss, and anemia. Treatment consists of a gluten-free diet.

Joints
Rheumatoid arthritis: Inflammation of joints and tendons that is distinguished from osteoarthritis, which is due to “wear and tear” over time, causing the cartilage lining joints to break down.

Skin
Vitiligo (leukoderma): Painless white patches of skin that appear around the hands, feet, arms, face, and lips. In severe cases, there is loss of the majority of pigment throughout the body.

Alopecia Areata: Typically patches of scalp hair are lost. It is the most common cause of hair loss in those under 20. It usually affects the scalp. Hair grows back, but the condition can recur. Treatment is not always necessary and includes injecting steroids into the affected area(s).