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What is Riedels thyroiditis and explain in detail?
Riedels thyroiditis, is a chronic form of thyroiditis. It is now believed that Riedels thyroiditis is one manifestation of a systemic disease that can affect many organ systems called IgG4-related disease. It is often a multi-organ disease affecting pancreas, liver, kidney, salivary and orbital tissues and retroperitoneum. The hallmarks of the disease are fibrosis and infiltration by IgG4 secreting plasma cells.

Signs and symptoms
Pathophysiology
Riedels thyroiditis is characterized by a replacement of the normal thyroid parenchyma by a dense fibrosis that invades adjacent structures of the neck and extends beyond the thyroid capsule