Retropharyngeal and Parapharyngeal Abscess

Deep neck space abscesses involving the retropharyngeal space (between the buccopharyngeal fascia and prevertebral fascia) and parapharyngeal space (lateral to the pharynx, extending from skull base to hyoid) represent serious infections with potential life-threatening complications including airway obstruction, mediastinitis, jugular vein thrombosis (Lemierre syndrome), and carotid artery erosion.

Etiology in children most commonly involves spread from upper respiratory infection or pharyngitis (group A streptococcus, S. aureus, anaerobes), while adults typically develop infections from dental sources, peritonsillar abscess extension, foreign body, or trauma. Polymicrobial infections with anaerobes (Fusobacterium, Prevotella) are common.

Diagnosis combines clinical examination with contrast-enhanced CT imaging of the neck (gold standard) showing rim-enhancing fluid collections with surrounding edema. Management includes airway protection, broad-spectrum IV antibiotics covering gram-positive cocci, anaerobes, and gram-negative organisms (e.g., ampicillin-sulbactam or clindamycin plus ceftriaxone), and surgical drainage either transorally or via external cervical approach for larger abscesses or those involving danger spaces.