Branchial-cleft sinus presenting with a retropharyngeal abscess for a newborn: a case report.

A retropharyngeal abscess rarely occurs in the neonate. We report a neonate without apparent trauma who presented with a left neck mass and respiratory distress at the fourth day of age. A lateral neck X-ray revealed a widened retropharyngeal space. A neck computed tomography (CT) scan revealed a space-occupying lesion with air content in the left retropharyngeal area, although direct laryngoscopy, endoscopy, and a pharyngoesophagogram did not demonstrate the presence of any fistula tract. Due to the high index of suspicion for an aero-digestive tract fistula, diluted contrast medium was injected into the cyst while performing a CT-guided aspiration, and opacification was found in the oropharynx, thus a branchial-cleft sinus appeared to be most likely. The follow-up neck CT scan revealed no evidence of any recurrence. We suggest that CT-guided aspiration and cystography are useful for the diagnosis and treatment of some neonatal neck cystic lesions.