Peritonsillar abscess

Peritonsillar abscess or quinsy is the most common deep neck infection, almost always secondary to acute or recurrent tonsillitis.

Peritonsillar abscesses are most common in 20-40 year-olds with a predominance for males and for smokers. It is less common in children but immunosuppression increases the risk of development 2,3.

Clinical features include a unilateral odynophagia, dysphagia, voice changes (sometimes classically referred to as a ‘hot potato’ voice), trismus, and excessive drooling 5. Additionally, patients may be systemically unwell with fever and malaise 5.

Peritonsillar abscess is usually a complication of tonsillitis and thus has a similar clinical presentation and infective aetiology 4. The most common pathogens are those that cause tonsillitis, namely beta-haemolytic Streptococci, with Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae also common causes 1

Infection extends through the fibrous capsule of the tonsil entering the peritonsillar space, located between the tonsillar capsule and superior pharyngeal constrictor muscle. Further extension may occur into the parapharyngeal, masticator, and/or submandibular spaces.

Most abscess develop in the superior pole of the tonsil.

  • rim-enhancing fluid collection within an enlarged and inflamed tonsil 1
  • 75% specific and 100% sensitive at diagnosing peritonsillar abscess 1
  • false positives are due to the similar appearances of peritonsillar abscess and phlegmon

Peritonsillar abscesses almost always require surgical aspiration or incision and drainage in comparison to tonsillitis, which is normally managed with antibiotics.

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Article information

rID: 26209
System: Head & Neck
Synonyms or Alternate Spellings:
  • Tonsillar abscess
  • Quinsy
  • Peritonsillar abscesses

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