Riedel's thyroiditis, also called Riedel's struma is a chronic form of thyroiditis

Thyroiditis

Thyroiditis is the inflammation of the thyroid gland. The thyroid gland is located on the front of the neck below the laryngeal prominence, and makes hormones that control metabolism.-Classification:...

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It is believed to be a form of autoimmune thyroiditis

Autoimmune thyroiditis

Autoimmune thyroiditis is a form of thyroiditis associated with an autoimmune disease where the body treats the thyroid gland and sometimes the hormones it produces as foreign bodies, therefore rejecting and attacking both.-Treatment:...

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Pathophysiology

Riedel's thyroiditis is characterized by a replacement of the normal thyroid parenchyma by a dense fibrosis

Fibrosis

Fibrosis is the formation of excess fibrous connective tissue in an organ or tissue in a reparative or reactive process. This is as opposed to formation of fibrous tissue as a normal constituent of an organ or tissue...

 that invades adjacent structures of the neck and extends beyond the thyroid capsule. This makes the thyroid gland stone-hard and fixed to adjacent structures. The inflammatory process infiltrates muscles and causes symptoms of tracheal compression. Surgical treatment is required to relieve tracheal or esophageal obstruction.

A shared mechanism with retroperitoneal fibrosis

Retroperitoneal fibrosis

Retroperitoneal fibrosis or Ormond's disease is a disease featuring the proliferation of fibrous tissue in the retroperitoneum, the compartment of the body containing the kidneys, aorta, renal tract and various other structures. It may present with lower back pain, renal failure, hypertension, deep...

 and sclerosing cholangitis has been suggested.

Prevalence

Riedel's thyroiditis is classified as rare. Most patients remain euthyroid, but approximately 30% of patients become hypothyroid and very few patients are hyperthyroid. It is most seen in women.

Treatment

Therapy usually consists of prednisone

Prednisone

Prednisone is a synthetic corticosteroid drug that is particularly effective as an immunosuppressant drug. It is used to treat certain inflammatory diseases and some types of cancer, but has significant adverse effects...

(?), nonetheless some cases may require surgery. Tamoxifen

Tamoxifen

Tamoxifen is an antagonist of the estrogen receptor in breast tissue via its active metabolite, hydroxytamoxifen. In other tissues such as the endometrium, it behaves as an agonist, hence tamoxifen may be characterized as a mixed agonist/antagonist...

 has been proposed as part of a treatment plan.

Treatment is directed to surgical relief of compressive symptoms. Tamoxifen may also be beneficial.
-Harrison's principle of internal medicine, 17th

The type Surgery which is indicated here is isthmectomy.

Eponym

It is named for Bernhard Riedel

Bernhard Moritz Carl Ludwig Riedel

Bernhard Moritz Carl Ludwig Riedel was a German surgeon who was a native of Teschentin, Grossherzogtum Mecklenburg. He graduated from the University of Rostock in 1872, and for the next three years was Prosector at Rostock under Friedrich Sigmund Merkel...

. He first recognized the disease In 1883 and published its description in 1896.