Clinical case seminar: Riedel's thyroiditis: report of a case complicated by spontaneous hypoparathyroidism, recurrent laryngeal nerve injury, and Horner's syndrome.

A 42-yr-old woman presented with hyperthyroidism and a large, firm, irregular goiter. Within a few weeks she became hypothyroid. Five months later she developed increasingly severe neck pain and compressive symptoms. The goiter had become rock hard. A fine needle aspiration biopsy showed features of chronic thyroiditis and fibrosis. She partially responded to a course of glucocorticoids. Tamoxifen was added, with marked improvement in goiter size and pain. Both medications were tapered off. Two months later the patient experienced paresthesias of the fingertips, perioral numbness, and a seizure. She was found to have spontaneous primary hypoparathyroidism. Three months later the patient became hoarse and experienced difficulty in breathing. She was found to have a massively enlarged thyroid with compression of the right internal jugular vein and encasement of the right carotid artery as well as tracheal narrowing. She also had right vocal cord paralysis due to recurrent laryngeal nerve involvement. Because of airway compromise, an emergency isthmusectomy was performed, and the patient was given a postoperative course of glucocorticoids with gradual improvement. Postoperative diagnosis was Riedel's thyroiditis. Two months later she presented with near-syncope and was found to have bradycardia, hypotension, and right Horner's syndrome, presumably due to compression of the right carotid sheath. She was given i.v. glucocorticoids and tamoxifen. Six months later and 18 months after her initial presentation, the patient is doing remarkably well. Her goiter has regressed by more than 50%, and she no longer has any pain or difficulty breathing. She remains a little hoarse and has persistent hypothyroidism and hypoparathyroidism. She is taking prednisone (5 mg, this is being tapered very slowly) and tamoxifen (20 mg) daily. This case illustrates the protean manifestations of Riedel's thyroiditis, a rare but fascinating disease. The epidemiology of this disease, its pathophysiology and complications, and the roles of surgery and medical therapy are reviewed.