Peritonsillar abscess
Peritonsillar abscess is the most common deep-space neck infection, presenting with unilateral sore throat, trismus, a muffled hot potato voice, and uvula deviation away from the affected side, treated with prompt drainage plus antibiotics covering group A streptococcus, Staphylococcus aureus, and oral anaerobes.
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What this article covers
- Overview
Peritonsillar abscess is a collection of pus between the tonsillar capsule and the superior constrictor muscle: it is the most common deep-space infection of the head and neck and typically develops…
- Epidemiology
Most common in young adults: the classic presentation is described in patients usually older than 10 years, distinguishing the age distribution from retropharyngeal abscess, which is most common from 6 months to 6 years of age.
- Risk factors
Recent or recurrent streptococcal pharyngitis or tonsillitis: the abscess classically arises as a suppurative complication of untreated or inadequately treated pharyngitis, with group A streptococcus able to persist in tonsillar tissue.
- Pathophysiology
Infection begins in the tonsil and spreads locally: acute tonsillitis or pharyngitis progresses to cellulitis of the peritonsillar tissue and then to frank abscess formation between the tonsillar capsule and the superior constrictor muscle.
- Clinical features
Severe, unilateral sore throat with dysphagia and odynophagia: pain is characteristically worse on one side of the neck than the other, often with referred pain to the ipsilateral ear.
- Differential diagnosis
Retropharyngeal abscess: also presents with fever, trismus, and a muffled "hot potato" voice, but typically affects children 6 months to 6 years old, causes neck swelling with a preference to sit up…
- Diagnosis
Peritonsillar abscess is a clinical diagnosis: the combination of unilateral peritonsillar bulging with medial tonsillar displacement and contralateral uvular deviation, trismus, muffled voice, and…
- Management
First, secure source control with drainage; this is the primary treatment and should not be delayed for antibiotics alone.
- Complications
Airway compromise: from extension of infection into the deep neck spaces, the most feared complication and the reason drainage is not deferred.
- Prognosis
Excellent with prompt drainage and antibiotics: most patients improve rapidly once the abscess is evacuated and appropriate antibiotics are started.
- Prevention
Treat streptococcal pharyngitis promptly with a full antibiotic course to reduce the risk of suppurative complications, including peritonsillar abscess; appropriate antibiotic treatment of bacterial…
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