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The typical clinical presentation of peritonsillar abscess is a severe unilateral sore throat associated with fever and a muffled “hot potato” voice. Malaise, dysphagia, and otalgia are also often present. Swallowing is painful, which sometimes leads to pooling of saliva or drooling. Trismus, difficulty opening the mouth because of pain from the inflammation, may be present. The oropharyngeal exam reveals an extremely swollen tonsil with the displacement of the uvula to the unaffected side and a bulging soft palate on the affected side. The patient may have markedly tender cervical lymphadenitis on the affected side.


  1. A peritonsillar abscess usually begins as acute, exudative tonsillitis that progresses to cellulitis and eventually to abscess formation. The abscess may occur without preceding infection via obstruction of the Weber glands, a group of salivary glands in the soft palate.

  2. It is the most common deep infection of head and neck, accounting for approximately 30% of abscesses of the head and neck.

  3. Occurs primarily in young adults between the ages of 20 and 40 years

  4. Peritonsillar abscesses are polymicrobial. Common organisms include:

    1. Aerobic bacteria

      1. Group A streptococci

      2. Staphylococcus aureus

      3. Haemophilus influenzae

    2. Anaerobic bacteria

      1. Fusobacterium

      2. Peptostreptococcus

      3. Pigmented Prevotella species

      4. Veillonella


  1. Diagnosis of peritonsillar abscess can be made clinically without laboratory data or imaging in patients with a typical presentation

    1. Symptoms

      1. Fever

      2. Malaise

      3. Severe sore throat (usually asymmetric)

      4. Dysphagia

      5. Ipsilateral otalgia

    2. Signs

      1. Erythematous, swollen soft palate with uvula deviation and an enlarged tonsil

      2. Trismus (present in nearly 66% of patients with peritonsillar abscesses)

      3. Drooling

      4. Muffled “hot potato” voice

      5. Rancid or fetor breath

      6. Cervical lymphadenitis

  2. Culture of pus from abscess drainage can confirm the diagnosis. The rate of culture positivity from peritonsillar abscess in the literature ranges from < 50% to 100%.

  3. Laboratory evaluation

    1. Laboratory evaluation is not necessary to make the diagnosis but may help gauge the level of illness and direct therapy.

    2. Testing usually includes:

      1. Complete blood count

      2. Routine throat culture for group A streptococci

      3. Gram stain, culture, and susceptibility testing of abscess fluid, especially in patients with persistent infection or diabetes or in those who are immunocompromised.

  4. Imaging

    1. Generally not necessary to make a diagnosis but may be considered in the following cases:

      1. Suspected spread beyond peritonsillar space

      2. Inability to successfully examine the pharynx because of trismus

      3. Monitoring patients unresponsive to initial treatment with antibiotics and drainage

    2. The preferred imaging modality is CT with IV contrast.

      1. Sensitivity, 100%

      2. Specificity, 75%

      3. LR+, 4

      4. LR–, 0

    3. Intraoral ultrasonography may be used to distinguish peritonsillar abscess from cellulitis and guide needle aspiration.

      1. Sensitivity, 89–95%

      2. Specificity, 79–100%


  1. Drainage, antibiotic therapy, and supportive care are the mainstays of therapy.

    1. Randomized, controlled trials have shown that needle aspiration and incision and drainage are equally effective.

    2. Rates of re-collection and failed resolution in 1–2 days were comparable at 10% for both procedures.

    3. Needle ...

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