Review Question - QID 107548

This patient with sore throat, fever, uvular deviation and an ultrasound demonstrating a fluid collection most likely has a peritonsillar abscess.

Peritonsillar abscess (PTA) typically occurs as a complication of pharyngitis or tonsillitis. Most often, PTA develops as a complication of bacterial pharyngitis, with Group A Streptococcus and anaerobic bacterial species being the most common culprits. Patients will typically report a history of a persistent sore throat, with associated fevers and chills, trismus, odynophagia and vocal changes. The characteristic vocal changes associated with PTA are often described as a "hot potato" voice. Exam typically reveals pharyngitis with exudates, and an obviously edematous tonsil. Deviation of the uvula from the midline, as is present in this patient, is a characteristic feature. The diagnosis can be made clinically, but ultrasound or CT imaging may be used to confirm the diagnosis, better characterize the size of the abscess and guide drainage. Treatment consists of abscess drainage, either with needle aspiration or incision and drainage, and antibiotic therapy. Amoxicillin-clavulanic acid is generally given orally, and ampicillin-sulbactam can be given for patients requiring intravenous antibiotics.

Galioto discusses diagnosis and treatment of patients with peritonsillar abscess. Peritonsilar abscess is seen mostly in young adults. Diagnosis is made via history and physical exam; needle aspiration for pus may be utilized if the presentation is ambiguous. The most common offending organisms include Group A streptococcus and anaerobes. Treatment includes drainage of the abscess, antibiotics (amoxicillin-clavulanic acid) and fluids. Hospitalization is rare and is usually required for re-hydration and pain control.

Mazur et al. discuss the epidemiology and microbiology of peritonsillar abscess. In their case-control study they found that the average age of patients with peritonsillar abscess was 31-years-old. Smoking and prior history of tonsillitis or pharyngitis were the most significant risk factors. Most cultured specimens were mono bacterial with S. pyogenes being most common.

Figure A demonstrates a peritonsillar abscess of the right palatine tonsil. Note the obvious edema and erythema of the right tonsil, and the deviation of the uvula from the midline.

Figure B shows an ultrasound image of the tonsil with findings characteristic of PTA. Note the tissue edema and fluid collection with loculations and debris.

Incorrect Answers:
Answer 1: Infectious mononucleosis often presents with an exudative pharyngitis that may appear similar to bacterial pharyngitis. However, pronounced unilateral tonisllar swelling, deviation of the uvula, and a fluid collection on ultrasound would not be expected.

Answer 3: Peritonsillar cellulitis is a bacterial infection of the surface of the tonsil. While tonsilar erythema and edema are common, uvular deviation and fluid collection visualized on ultrasound point toward peritonsillar abscess as the diagnosis.

Answer 4: Retropharyngeal abscess is a deep space infection of the neck in the retropharyngeal space. The diagnosis is more common in younger children and presents with swelling of the posterior pharynx and pain with neck movement.

Answer 5: Viral pharyngitis is a common cause of sore throat. Patients typically have pharyngeal erythema with associated cough and may have lymphadenopathy. However, this patient's exam and imaging findings point toward PTA as the diagnosis.

Bullet Summary:
Peritonsillar abscess presents with sore throat, tonsillar swelling and uvular deviation.