DESCRIPTION

A relatively rare but potentially life-threatening infection occurring in the potential space between the posterior pharyngeal wall and prevertebral fascia

EPIDEMIOLOGY

• Winter-spring seasonality
• Children <5 years old are at highest risk.
• 4.1 per 100,000 children <20 years old
• Male-to-female ratio: 2:1

ETIOLOGY

• Infectious: Cultures often reveal multiple organisms (polymicrobial).
• The predominant organisms isolated include the following:
  • Streptococcus (group A and others)
  • Staphylococcus aureus
  • Various anaerobic species (e.g., Prevotella, Peptostreptococcus, Fusobacterium, Veillonella)
• Many of the isolates are β-lactamase producers.

PATHOPHYSIOLOGY

• Most infections result from pharyngitis or supraglottitis and occur because of suppuration of the retropharyngeal lymph nodes, which lie in two paramedian chains and drain the nasopharynx, adenoids, posterior paranasal sinuses, middle ear, and eustachian tube.
• These lymph gland chains are prominent in childhood but atrophy before puberty; thus, retropharyngeal abscesses are most common in infancy and early childhood.
• Cellulitis of the retropharyngeal area leads to formation of a phlegmon, which matures into an abscess.
• Other sources of infection in this space, often seen in older children and adolescents, include penetrating trauma of the posterior pharynx (e.g., foreign object aspiration, dental procedures, attempts at intubation).
• Extension of infection into this space can arise from vertebral body osteomyelitis or a dental abscess.