Peritonsillar abscess (PTA), or quinsy, is the most common deep head and neck infection. Although most occur in young adults, immunocompromised and diabetic patients are at increased risk. Most PTAs develop as a complication of tonsillitis or pharyngitis, but may also result from odontogenic spread, recent dental procedures, and local mucosal trauma.
The pathogens involved are similar to those causing tonsillitis, especially streptococcal species, but many infections are polymicrobial and involve anaerobic bacteria (Fusobacterium). Patients present with a fever, severe sore throat that is often out of proportion to physical findings, localization of symptoms to one side of the throat, trismus, drooling, dysphagia, dysphonia, fetid breath, and ipsilateral ear pain.
During the early stages, the tonsil and anterior pillar are erythematous, appear full, and may be shifted medially. Later, the uvula and soft palate are shifted to the contralateral side. The tonsillar pillar may feel fluctuant and tender.
Management and Disposition
In most patients, needle aspiration performed as the sole surgical drainage procedure produces a satisfactory outcome. Alternative surgical drainage procedures—including incision and drainage and abscess tonsillectomy—can be performed by an otolaryngologist or oral surgeon. Most PTAs are managed in the outpatient setting with oral antibiotics following drainage. Patients who are immunocompromised, have airway involvement, appear toxic, or cannot tolerate oral intake require admission for rehydration, parenteral antibiotics, and specialty consultation.
Early Peritonsillar Abscess. Edema and marked erythema of the left tonsillar pillar in early peritonsillar abscess. (Photo contributor: Kevin J. Knoop, MD, MS.)
Peritonsillar Abscess. Acute peritonsillar abscess showing medial displacement of the uvula, palatine tonsil, and anterior pillar. (Photo contributor: Lawrence B. Stack, MD.)
The value of culturing aspirates is questionable, with a review of several studies showing no clinical benefit from the cultures unless the patient is immunocompromised.
ED ultrasound along with palpation of the mass is a valuable adjunct in confirming diagnosis and verifying anatomical landmarks prior to aspiration.
A contrasted CT scan of the neck will confirm the presence of a PTA if the diagnosis is uncertain.
Peritonsillar Abscess—Ultrasound. Ultrasound demonstrates size and location of abscess, in addition to confirming relationship to vascular structures. Over 2 mL of pus was aspirated from this abscess. (Photo contributor: Kevin J. Knoop, MD, MS.)
Peritonsillar Phlegmon. Marked erythema of the tonsillar pillars is seen in this patient currently on oral penicillin. No swelling or fluctuance is present. (Photo contributor: Lawrence B. Stack, MD.)