evidence: Hashimoto thyroiditis, like Graves disease, is sometimes associated with other autoimmune disorders, including Addison disease (adrenal insufficiency), type 1 diabetes mellitus, hypoparathyroidism, vitiligo, premature graying of hair, pernicious anemia, systemic rheumatic diseases (eg, rheumatoid arthritis, systemic lupus erythematosus, Sjögren syndrome), celiac disease, and type 2 polyglandular deficiency syndrome (Schmidt syndrome—a combination of Addison disease with hypothyroidism secondary to Hashimoto thyroiditis and/or type 1 diabetes mellitus). There may be an increased incidence of thyroid tumors, rarely thyroid lymphoma. Pathologically, there is extensive infiltration of lymphocytes with lymphoid follicles and scarring. [...] Treatment of Hashimoto Thyroiditis Hashimoto thyroiditis is autoimmune inflammation of the thyroid.