• Inflammation of the thyroid gland. This category includes Hashimoto thyroiditis, Riedel thyroiditis, acute thyroiditis, subacute thyroiditis, and radiation-induced thyroiditis.
  NCI
  U.S. National Cancer Institute, 2021
• Inflammation of the thyroid gland. Thyroiditis may be an autoimmune disease that affects the thyroid gland over time, causing hypothyroidism (too little thyroid hormone). A temporary form of thyroiditis may also occur after the birth of a baby, or when viral or bacterial infections spread to the thyroid.
  NCI Dictionary of Cancer Terms
  U.S. National Cancer Institute, 2021
• Inflammation of the thyroid gland. Types of thyroiditis include Hashimoto's thyroiditis, subacute thyroiditis, and postpartum or silent thyroiditis.
  Harvard Dictionary of Health Terms
  Harvard Medical Publishing, 2011
• Inflammatory diseases of the THYROID GLAND. Thyroiditis can be classified into acute (THYROIDITIS, SUPPURATIVE), subacute (granulomatous and lymphocytic), chronic fibrous (Riedel's), chronic lymphocytic (HASHIMOTO DISEASE), transient (POSTPARTUM THYROIDITIS), and other AUTOIMMUNE THYROIDITIS subtypes.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• The broad category of thyroiditis includes the following inflammatory diseases of the thyroid gland: (1) acute suppurative thyroiditis, which is due to bacterial infection; (2) subacute thyroiditis, which results from a viral infection of the gland; and (3) chronic thyroiditis, which is usually autoimmune in nature. In childhood, chronic...
  Medscape
  WebMD, 2025
• Thyroiditis, any of many inflammatory diseases of the thyroid gland. Several nonspecific types of thyroiditis, both acute and chronic, may be caused by bacterial and viral organisms. There are, however, two specific, noninfectious types of thyroiditis: (1) Hashimoto's disease, or struma lymphomatosa, and (2) granulomatous thyroiditis,...
  Encyclopedia Britannica
  Encyclopedia Britannica, Inc., 2025