Nine cases of piriform sinus fistula with acute suppurative thyroiditis

Objective: Acute suppurative thyroiditis is a disease of an infection originated from the piriform sinus via congenital fistula. The purposes of this study are the establishment of accurate and necessary examinations for the diagnosis and necessary treatment for complete remission of this disease. Methods: We reported nine cases with acute suppurative thyroiditis who were treated by operation. Preoperative examinations and operative procedures for nine cases were investigated. Results: A congenital fistula was detected in seven of nine patients preoperatively, and in all seven patients, the fistula was detected during the operation. Serum thyroglobulin was elevated in four of five patients who were examined the serum level. Ultrasonogram was performed in eight cases, and localized swelling of the thyroid lobe was observed in all cases. No inflammatory recurrence was observed in eight cases, and recurrence was observed in one case where complete fistelectomy was not performed. Conclusion: Measurements of serum thyroglobulin, ultrasonography, and pharyngoesophagography were useful in the diagnosis of acute suppurative thyroiditis. Complete removal of the fistula with or without affected thyroid lobe is necessary to prevent recurrent suppuration.