De Quervain Thyroiditis

In general, thyroiditis is defined as an inflammation of the thyroid gland. There are several kinds of thyroiditis, and they can be associated with either increased, decreased, or normal thyroid function. Furthermore, they can be classified as painful or painless, depending on the etiology. Differentiating between the different kinds is dependent on the clinical setting, medical and family history, how fast the symptoms progressed, and most importantly, the presence or absence of neck pain. Typically, painful thyroiditis is caused by radiation, trauma, or infection, while painless thyroiditis is caused by autoimmune diseases or medications. Painful thyroiditis can be further divided into subacute granulomatous (de Quervain) thyroiditis, suppurative thyroiditis, and thyroiditis caused by radiation/trauma. Painless thyroiditis can be subdivided into Hashimoto thyroiditis, postpartum thyroiditis, subacute lymphocytic thyroiditis, drug-induced (amiodarone, interferon-alpha, interleukin 2, lithium) thyroiditis, and Riedel (fibrosis) thyroiditis. This article will focus on subacute granulomatous thyroiditis, also known as subacute thyroiditis, painful thyroiditis, subacute nonsuppurative thyroiditis, giant cell thyroiditis, or de Quervain thyroiditis. It is an infrequent cause of hyperthyroidism. The common symptoms are neck pain or discomfort, tenderness to palpation, and a predictable course of hyperthyroidism followed by euthyroidism, hypothyroidism, and back to euthyroidism.