Fourth branchial arch fistula and suppurative thyroiditis: a life-threatening infection.

A potentially life-threatening case of recurrent left-sided thyroid abscess formation secondary to a fourth branchial arch sinus fistula is presented. The patient developed a reversible left vocal fold palsy during an acute episode of suppurative thyroiditis requiring a temporary tracheostomy due to a compromised airway. Investigations commonly used to demonstrate this anomaly may fail to confirm the diagnosis as in the case presented and exploratory surgery with excision of the fistulous tract should still be considered. We describe a method of repairing the pharyngeal opening to reduce the risk of recurrence or pharyngeal leak.