Acute suppurative thyroiditis with bilateral piriform sinus fistulae.

Although there are many possible routes of infection in AST, the clinician must be aware of a possible fistula between the piriform sinus and the perithyroidal space--especially in patients with recurrent episodes of AST. Diagnosis of this congenital tract requires a high index of suspicion and radiographic demonstration by a barium swallow or endoscopic visualization. Effective treatment of AST with intravenous antibiotics and appropriate surgical intervention have greatly reduced the mortality and secondary complications. Complete fistulectomy, however, is required for permanent cure.