Subacute thyroiditis

**Definition:** A self-limited thyroiditis associated with a triphasic clinical course of hyperthyroidism, hypothyroidism, and return to normal thyroid function. It is thought to be caused by a viral infection.

**Inclusions:** - de Quervain thyroiditis - giant-cell thyroiditis - granulomatous thyroiditis

**Exclusions:** - Autoimmune thyroiditis