Which of the following is true about Reidel's thyroiditis: (A) Fibrosis involves the thyroid and surrounding neck structures, (B) Patient presents with hard fixed thyroid mass, (C) It may be associated with retroperitoneal fibrosis, (D) All the above
Answer is D. Answer- D. All the aboveA rare disorder characterized by extensive fibrosis involving the thyroid and contiguous neck structures.The presence of a hard and fixed thyroid mass clinically simulates a thyroid carcinoma.It may be associated with fibrosis in other sites in the bodn such as the retroperitoneum, and appears to be another manifestation of a systemic autoimmune IgG4-related disease, which is associated with fibrosis and tissue infiltration by plasma cells producing IgG4.