Peritonsillar abscess and cellulitis are acute pharyngeal infections most common among adolescents and young adults. Symptoms are severe sore throat, trismus, "hot potato" voice, and uvular deviation. Diagnosis requires needle aspiration. Treatment includes broad-spectrum antibiotics, drainage of any pus, hydration, analgesics, and, occasionally, acute tonsillectomy.
Etiology of Peritonsillar Abscess and Cellulitis
Abscess (quinsy) and cellulitis probably represent a spectrum of the same process in which bacterial infection of the tonsils and pharynx spreads to the soft tissues. Infection is virtually always unilateral and is located between the tonsil and the superior pharyngeal constrictor muscle. It usually involves multiple bacteria. Streptococcus and Staphylococcus species are the most frequent aerobic pathogens; Bacteroides species is the predominant anaerobic pathogen.
Symptoms and Signs of Peritonsillar Abscess and Cellulitis
DR P. MARAZZI/SCIENCE PHOTO LIBRARY
Symptoms include gradual onset of severe unilateral sore throat, dysphagia, fever, otalgia, and asymmetric cervical adenopathy. Trismus, "hot potato" voice (speaking as if a hot object was in the mouth), a toxic appearance (eg, poor or absent eye contact, irritability, inability to be consoled or distracted, fever, anxiety), drooling, severe halitosis, tonsillar erythema, and exudates are common. Abscess and cellulitis both cause swelling above the affected tonsil, but abscess causes a more discrete bulge, with deviation of the soft palate and uvula and pronounced trismus.
Diagnosis of Peritonsillar Abscess and Cellulitis
Needle aspiration
Sometimes CT
Peritonsillar cellulitis is recognized in patients who have a severe sore throat and who have the following:
Trismus
"Hot potato" voice
Uvular deviation
All such patients require needle aspiration of the tonsillar mass and cultures. Aspiration of pus differentiates abscess from cellulitis. Point-of-care ultrasonography can be used for diagnosis and to determine the optimal location for aspiration or incision and drainage; sensitivity is high, but specificity is only moderate (1).
CT of the neck can help confirm the diagnosis when the physical examination is difficult or the diagnosis is in doubt, particularly when the condition must be differentiated from a parapharyngeal infection or other deep neck infection.
Diagnosis reference
1. Kim DJ, Burton JE, Hammad A, et al: Test characteristics of ultrasound for the diagnosis of peritonsillar abscess: A systematic review and meta-analysis. Acad Emerg Med 30 (8):859–869, 2023. doi: 10.1111/acem.14660
Treatment of Peritonsillar Abscess and Cellulitis
Antibiotics
Drainage of abscess
Cellulitis
Abscesses are usually incised and drained in the emergency department using thorough local anesthesia and sometimes procedural sedation; many clinicians believe needle aspiration alone provides adequate drainage. Ultrasound guidance is sometimes used when the diagnosis of abscess is unclear or when the abscess is small (< 1 cm). Although most patients can be treated as outpatients, some need brief hospitalization for parenteral antibiotics, IV hydration, and airway monitoring.
Rarely, an immediate tonsillectomy is done, particularly in a young or uncooperative patient who has other indications for elective tonsillectomy (eg, history of frequently recurrent tonsillitis or obstructive sleep apnea). Otherwise, if patients have also had recurrent tonsillitis, elective tonsillectomy is done 4 to 6 weeks later to prevent abscess recurrence.
