: A variety of inflammatory disorders of thyroid that can cause hyper or hypothyroidism, or resolve completely.

• The types include Hashimoto’s lymphocytic thyroiditis (most common and often presenting as diffuse asymptomatic goitre), Subacute granulomatous type, related to viral infection, with acute painful enlargement (initially hyper, later hypo thyroidism, and eventually resolving), rare Chronic fibrous Riedel’s thryroiditis (hypo thyroid state with local invasion causing dysphagia, dyspnoea) and miscellaneous like Suppurative, post-radiation types.
• Variable thyroid function results, with discrepancy between T4 and radioactive iodine uptake. (low uptake but raised T3 and T4 in subacute form.), and elevated antithyroid (anti TPO), antibodies in Hashimoto’s. Antimicrosomal antibodies detected in >90% of cases with Hashimoto’s thyroiditis, and 50-80% in those with silent thyroiditis. Radioactive iodine uptake in 24 hours, is raised in Grave’s disease as opposed to low or normal levels in thyroiditis.
• Fine needle aspiration cytology (FNAC) for confirmation of type.
• Hashimoto’s associated with other auto-immune states, diabetes, Addison’s disease, Pernicious anemia, Vitiligo, biliary cirrhosis etc.