In the article, “Acute exacerbation of Hashimoto's thyroiditis in a patient treated with dimethyl fumarate for multiple sclerosis: A case report”,[ which appeared in Volume 98, Issue 17 of Medicine, 1b needs to be 1a in two sentences in the Case section. Theese sentence should appear as “She was previously treated for 3 years with interferon-β (IFN-β) 1a 22 mg subcutaneously 3 times a week from which she was switched to DMF due to flu-like syndrome side effects” and “During treatment with IFN-β 1a as well as before beginning treatment with DMF, findings of thyroid function test were within normal limits, with positive antithyroid antibodies (Table 1).”