Retropharyngeal Abscess

Retropharyngeal abscess is usually seen in infants or young children. It may be caused by an upper respiratory tract infection that then results in adenitis in the retropharyngeal nodes, which then suppurates and forms an abscess.

The abscess is limited to one side of the midline because of the median raphe of the buccopharyngeal fascia. Abscesses are most often caused by:

• Beta-hemolytic streptococci, Staphylococcus aureus, Haemophilus parainfluenzae
• Anaerobic organisms, e.g. Bacteroides

Early recognition and aggressive management are essential because there is a significant morbidity and mortality.

• Uncommon and occurs much less commonly today than in the past because of the widespread use of antibiotics for suppurative upper respiratory infections.
• Once almost exclusively a disease of children, but is now seen increasingly in adults.

• May present with signs of airway obstruction. May rapidly progress to airways obstruction if not initially evident.
• Usually seen in an infant or young child with high fever, agitation, neck pain, malaise, fever, dysphagia, drooling, cough, respiratory distress, stridor.¹
• Stiff neck with head tilted to one side. Smooth bulge on one side of the midline of the posterior pharyngeal wall. Associated signs include tonsillitis, peritonsillitis, pharyngitis and otitis media.
• Symptoms in adults: sore throat, fever, dysphagia, neck pain, dyspneoa.
• Physical signs in adults: posterior pharyngeal oedema, neck stiffness, cervical adenopathy, fever, drooling, stridor.

• Retropharyngeal cellulitis
• Angioedema
• Dental infections
• Epiglottitis
• Foreign bodies
• Pharyngeal pouch
• Mediastinitis
• Infectious mononucleosis
• Otitis media, pharyngitis, pneumonia
• Croup
• Peritonsillar abscess

• Full blood count: white cell count very high
• CRP may also be very high
• Blood cultures: but often negative
• Culture of pus aspirated at the time of surgical drainage
• Lateral neck x-ray:
  • Widening of the retropharyngeal soft tissues; may also rarely may show a gas-fluid level, gas in the tissues or a foreign body.
  • Lateral neck x-ray findings may be misleading, especially in young children.
• CT scan of the neck with IV contrast:
  • Retropharyngeal abscess appears as a hypodense lesion in the retropharyngeal space with peripheral ring enhancement.
  • Obtain a CT scan of the neck with IV contrast when the findings on the lateral neck x-ray are equivocal but CT scan of the neck with IV contrast can also differentiate between retropharyngeal abscess and cellulitis.
  • The CT scan also shows the extent of the abscess and its relation to the great vessels.
• Chest x-ray; to identify aspiration pneumonia and mediastinitis.

• Urgent admission to hospital under care of an Ear Nose and Throat specialist.
• If a patient with signs of upper airway obstruction cannot be intubated, a surgical or needle cricothyrotomy may be required. A tracheostomy may also be required but this is rare.²
• Oxygen
• Intravenous fluids if dehydrated
• High dose antibiotics; initially high dose intravenous amoxicillin or erythromycin and later changed if necessary in line with culture results and clinical progress. Clindamycin has also been shown to be an effective initial treatment.³
• Surgical drainage of abscess by incision. Surgery may be required urgently but can otherwise be reserved for those who do not respond to antibiotic treatment.^2,3

• Airway obstruction
• Mediastinitis
• Pericarditis
• Aspiration pneumonia
• Epidural abscess
• Septicaemia
• Adult respiratory distress syndrome (ARDS)
• Erosion of the second and third cervical vertebrae
• Cranial nerve IX and/or XII deficits
• Septic thrombosis of jugular vein or haemorrhage secondary to erosion into carotid artery

• Prognosis is generally good if identified early, managed aggressively, and complications do not occur.
• Mortality rate may be as high as 40-50% in patients in whom serious complications develop.
• Once mediastinitis occurs, mortality approaches 50%, even with antibiotic therapy.