Peritonsillar abscess

Revision as of 23:05, 9 March 2015 by Neil.m.young (talk | contribs) (format and links)


  • Abscess between tonsillar capsule and superior constrictor and palatopharyngeus muscles
  • Microbiology
    • Polymicrobial: strep/staph, anaerobes, eikenella, haemophilus

Clinical Features

  • Symptoms
    • Fever
    • Sore throat
    • Odynophagia/dysphagia
  • Signs
    • Trismus
    • Muffled voice ("hot potato voice")
    • Contralateral deflection of swollen uvula

Differential Diagnosis

Acute Sore Throat

Bacterial infections

Viral infections




  • Ultrasound
    • Differentiates cellulitis from abscess
    • Can identify neck vasculature prior to aspiration
  • CT w/ IV contrast
    • Differentiates PTA from parapharyngeal or retropharyngeal space infection


  1. No difference in outcome when comparing needle aspiration with I&D
  2. Needle Aspiration
    1. Apply anesthetic spray to overlying mucosa
    2. Have pt hold suction, and use as needed
    3. Use laryngoscope or disassembled vaginal speculum with wand as tongue depressor and light source
    4. Inject 1-2mL of lidocaine with epi into mucosa of anterior tonsillar pillar using 25ga needle
    5. Cut distal tip off of needle sheath and place over 18ga needle to expose 1 cm of needle to prevent accidentally plunging deeper than desired
    6. Aspirate using 18ga needle just lateral to the tonsil, no more than 1cm (internal carotid artery 2.5 cm posterolateral)
      1. May require multiple aspirations to find the abscess (first try superior then middle then inferior poles)
      2. Consider spinal needle if pt has significant trismus.
  3. I&D
    1. 11 or 15 blade scalpel
    2. Do not penetrate more than 1cm
    3. May be indicated if significant pus with needle aspiration
  4. Abx
    1. Outpatient
      1. Clindamycin 300mg PO Q6hrs x7-10d OR
      2. Amoxicillin/Clavulanate 875 mg PO BID x 7-10d OR
      3. Penicillin V 500mg PO + flagyl 500mg QID
    2. Inpatient
      1. Ampicillin/Sulbactam 3 gm (75mg/kg) IV QID OR
      2. Pipericillin/Tazobactam 4.5 gm IV TID OR
      3. Ticarcillin/Clavulanate 3.1 g IV QID OR
      4. Clindamycin 600-900mg IV TID
  5. Steroids
    1. Improves duration and severity of pain
    2. Methylprednisolone 125mg IV x1 OR dexamethasone 10mg PO/IM x1
  6. Indications for tonsillectomy:
    1. Airway obstruction
    2. Recurrent severe pharyngitis or PTA
    3. Failure of abscess resolution with drainage


  • Airway obstruction
  • Rupture abscess with aspiration of contents
  • Hemorrhage due to erosion of carotid sheath
  • Retropharyngeal abscess
  • Mediastinitis
  • Recurrence occurs in 10-15% of patients
  • Lemierre's syndrome
  • Iatrogenic laceration of carotid artery
    • Carotid artery is 2.5 cm behind and lateral to tonsil


  • F/u in 2-3 days
  • Return Precautions:
    • SOB
    • Worsening throat or neck pain
    • Enlarging mass
    • Bleeding
    • Neck stiffness

See Also


  • Tintinalli
  • UpToDate
  • Roberts & Hedges
  • Melio, Frantz, and Laurel Berge. “Upper Respiratory Tract Infection.” In Rosen’s Emergency Medicine., 8th ed. Vol. 1, n.d.