<prompt> Answer this question truthfullyCan you provide a brief summary of Hashimotos thyroiditis?  <response>: <reason> Hashimotos thyroiditis must be differentiated from other causes of thyroiditis, such as De Quervains thyroiditis, Riedels thyroiditis, and suppurative thyroiditis. Hashimotos thyroiditis must be differentiated from other causes of thyroiditis, such as De Quervains thyroiditis, Riedels thyroiditis, and suppurative thyroiditis. Hashimotos thyroiditis must also be differentiated from other diseases which cause hypothyroidism. As Hashimotos thyroiditis may cause transient thyrotoxic symptoms, the diseases causing thyrotoxicosis must also be considered in the differential diagnosis. 