(Medicine) autoimmune disorder of the thyroid gland which can serve as a precursor to Graves' disease (characterized by deficient activity and enlargement of the thyroid gland)
Hashimoto's thyroiditis or chronic lymphocytic thyroiditis is an autoimmune disease where the body's own antibodies attack the cells of the thyroid.This disorder is believed to be the most common cause of primary hypothyroidism in North America. It occurs far more often in women than in men (10:1 to 20:1), and is most prevalent between 45 and 65 years of age. In European countries an atrophic form of autoimmune thyroiditis (Ord's thyroiditis) is more common than Hashimoto's thyroiditis.
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