Recurrent suppurative thyroiditis due to fourth branchial pouch sinus.

Acute suppurative thyroiditis is a rare disease in childhood. The etiology of this condition is not always obvious. The description of a pharyngeal pouch fistula extending from the pyriform sinus to the thyroid gland or perithyroid area, high-lighted the etiopathogenesis of some of the thyroiditis cases. Presented here are the clinical, radiological and pathological aspects of an internal pharyngeal fistula manifesting with recurrent suppurative thyroiditis, until it was completely removed. The clinical features of caudal branchial pouch remnants and their role in the development of acute suppurative thyroiditis is reviewed.