Antibodies Associated With Thyroid Disease

Antibodies, or immunoglobulins, are proteins your body uses to protect itself from foreign entities. Antibodies can cause your thyroid to work harder, block thyroid hormone or cause harmful inflammation.

Condition

• Hashimoto's thyroiditis develops when your immune system interprets your thyroid as foreign. Antibodies destroy thyroid cells and form scar tissue in your thyroid gland, enlarging it. Your thyroid cannot produce enough thyroid hormone, causing you to eventually become hypothyroid.

Risk

• According to "A Simple Guide to Thyroid Disorders" by Dr. Paul Ruggieri and Dr. Scott Isaacs, heredity is a major factor. 10 percent of people have thyroid auto-antibodies, which increases the risk of developing Hashimoto's thyroiditis. Hashimoto's thyroiditis is the most common form of inflammation of the thyroid due to antibodies turning against the thyroid.

Associations

• Graves' disease, type 1 diabetes, rheumatoid arthritis and lupus are other autoimmune disorders that are associated with Hashimoto's thyroiditis. Addison's disease and pernicious anemia are also conditions that tend to be associated with thyroid disease caused by antibodies turning on the thyroid.

Tgab

• An Antithyroid Antibodies Test, or ATA, is a blood test used to check for antibodies in your body that attack the thyroid. One of the antibodies is Tgab, or antithyroglobulin antibody. Tgab damages thyroglobulin, the main protein that stores thyroid hormone and interferes with production of thyroid hormone.

TPOAb

• TPOAb, or antithyroid peroxidase antibody, is another antibody the ATA test may find. TPOAb disrupts peroxidase, which is an enzyme that maintains the proper chemical balance for the production of thyroid hormone. (Reference 1, page 22-23)

TSI

• Thyroid Stimulating Immunoglobulin, or TSI, is an antibody the ATA test is searching for that can cause thyroid disease. TSI can cause Graves' disease and also an overactive thyroid.