Riedel's thyroiditis

Medical condition

Riedel's thyroiditis, is a chronic form of thyroiditis. It is now believed that Riedel's 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 retroperitoneal space. The hallmarks of the disease are fibrosis and infiltration by IgG4 secreting plasma cells.

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