De Quervain's thyroiditis: current concepts and a report of four cases

Introduction: De Quervain's subacute thyroiditis is a self-limiting granulomatous inflammatory disorder, which is thought to be virally induced in genetically predisposed individuals. It is characterized by thyroid pain and thyrotoxicosis, as well as by systemic symptoms like fever, hepatic cytolysis, and an elevated erythrocyte sedimentation rate. It is often mistaken for an upper respiratory tract infection.
Materials and methods: The authors review recent advances in the understanding of the pathogenesis and pathophysiology of De Quervain's subacute thyroiditis; risk factors for complications, with emphasis on relapses and end-stage hypothyroidism; differential diagnosis and the exclusion of other subtypes of thyroiditis; and current treatment options. Four cases of De Quervain's thyroiditis are then analyzed and compared with cases in the literature.
Discussion: In three of the patients, onset occurred in June and was probably related to a small, seasonal epidemic cluster. These cases were quite different from the fourth one, which occurred in October, suggesting that two distinct viruses might be involved. One of the patients presented a very rare complication, vocal-cord paralysis, which responded well to glucocorticoid therapy. Another presented with an even rarer post-partum form of painful thyroiditis.