Introduction
A peritonsillar abscess (PTA) is a localized accumulation of pus in the peritonsillar tissues that forms as a result of suppurative tonsillitis. An alternative explanation is that PTA is an abscess formed in a group of salivary glands in the supratonsillar fossa, known as Weber glands. The nidus of accumulation is located between the capsule of the palatine tonsils and the constrictor muscles of the pharynx. The anterior and posterior pillars, torus tubarius (superior), and pyriform sinus (inferior) form the boundaries of this potential peritonsillar space. Because it is composed of loose connective tissue, severe infection of this area may rapidly lead to formation of purulent material. Progressive inflammation and suppuration may extend to directly involve the soft palate, the lateral wall of the pharynx, and, occasionally, the base of the tongue.
Right peritonsillar abscess. The soft palate, which is erythematous and edematous, is displaced anteriorly. The patient has a "hot potato–sounding" voice.
Pus is aspirated through a wide-bore needle from the right peritonsillar abscess. An additional incision will be made to drain any other pus pockets.
Recent research
In a retrospective cohort study, Marom et al investigated how the characteristics of PTA may have changed over time.1 Examining data from 427 patients with PTA, the authors determined that the annual incidence of the condition was approximately 1 patient per 10,000 at the secondary hospital where the cases in the study were treated. PTA demonstrated no sex predilection, nor did it tend to occur more often on a particular side of the body. No seasonal predilection was found.
The cohort included 104 patients (24.4%) aged 40 years or older, with these individuals being more prone to complications and tending to have longer hospital stays than did the younger study patients. No anteceding pharyngotonsillitis was found in 102 patients (24%), and 283 patients (66%) had developed PTA in spite of prior antibiotic treatment. The investigators also found that the percentage of smokers in the cohort was greater than in the general population and that patients with PTA who smoked tended to have more complications than did the other patients.
According to the authors, the above results suggest that PTA tends to affect an older population than before, that its course in older individuals has become longer and worse, and that smoking may be a predisposing factor in its development.
History of the Procedure
Common sites of infection, PTAs have been described as early as the 14th century; however, only since the advent of antibiotics in the 20th century has the condition been described more extensively.
Problem
PTA usually is a complication of an acute tonsillitis. Inflammatory edema may lead to significant difficulty in swallowing. Dehydration frequently occurs secondary to the patient's avoidance of painful ingestion of food and liquids. Expansion of the abscess may lead to extension of the inflammation into adjacent fascial compartments of the head and neck, potentially leading to airway obstruction.
Frequency
The incidence of PTA in the United States is about 30 cases per 100,000 people per year, representing about 45,000 new cases each year. No accurate data are available internationally.
Although tonsillitis is a disease of childhood, only one third of PTA cases are found in this age group. The age of patients with the condition is variable, ranging from 1-76 years, with the highest incidence in persons aged 15-35 years.
No sexual or racial predilection exists.
Etiology
Any of the microorganisms that cause acute or chronic tonsillitis may be the causative organisms of a PTA. Most commonly, aerobic and anaerobic gram-positive organisms are identified by culture. Cultures of affected patients reveal group A beta-hemolytic streptococci as most prevalent. Next most commonly, staphylococci, pneumococci, and Haemophilus organisms are found. Finally, other microorganisms that can be cultured include lactobacilli, filamentous forms such as Actinomyces species, micrococci, Neisseria species, diphtheroids, Bacteroides species, and nonsporulating bacteria. Some evidence indicates that anaerobic bacteria frequently cause these infections.2
Pathophysiology
The pathophysiology of PTA is unknown. The most widely accepted theory is the progression of an episode of exudative tonsillitis first into peritonsillitis and then into frank abscess formation. Extension of the inflammatory process may occur in both treated and untreated populations. PTA also has been documented to arise de novo without any prior history of recurrent or chronic tonsillitis. A PTA also can be the presentation of an Epstein-Barr virus (ie, mononucleosis) infection.
Another theory proposes the origin of PTA in Weber glands. These minor salivary glands are found in the peritonsillar space and are thought to help in clearing debris from the tonsils. Should obstruction as a result of scarring from infection occur, tissue necrosis and abscess formation result, leading to PTA.
Presentation
History
Patients typically present with a history of acute pharyngitis accompanied by tonsillitis and worsening unilateral pharyngeal discomfort. Patients also may experience malaise, fatigue, and headaches. They often present with a fever and asymmetric throat fullness. Associated halitosis, odynophagia, dysphagia, and a "hot potato–sounding" voice occur.
Many patients present with ipsilateral referred otalgia with swallowing. Trismus (ie, a limitation in the ability to open the oral cavity) of varying severity is present in all cases, reflecting lateral pharyngeal wall and pterygoid musculature inflammation. Because of lymphadenopathy and cervical muscle inflammation, patients often experience neck pain and even a limitation in neck mobility. Clinicians need to be alerted to the diagnosis of a PTA in patients with persisting pharyngeal symptoms despite an adequate antibiotic regimen.
As the degree of inflammation and infection proceeds, symptoms include progression in the floor of the mouth, the parapharyngeal space, and the prevertebral space. Extension in the floor of the mouth is worrisome because of airway obstruction; the clinician must be aware of an eventual airway emergency.
Physical examination
The presentation may vary from acute tonsillitis with unilateral pharyngeal asymmetry to dehydration and sepsis. Most patients have severe pain. Examination of the oral cavity reveals marked erythema, asymmetry of the soft palate, tonsillar exudation, and contralateral displacement of the uvula.
In a retrospective study from the University of Ottawa, Kilty and Gaboury reported that in 50 adults with PTA, clinical signs that had a significant association with the lesion included uvular deviation (p <0.001), trismus (p <0.001), and inferior displacement of the superior pole of the tonsil (p <0.001) on the affected side.3
A PTA ordinarily is unilateral and located at the superior pole of the affected tonsil, in the supratonsillar fossa. At the level of the supratonsillar fold, the mucosa may appear pale and even show a small pimple. Palpation of the soft palate often reveals an area of fluctuance. Flexible nasopharyngoscopy and laryngoscopy are recommended in patients experiencing airway distress. The laryngoscopy is key to rule out epiglottitis and supraglottitis, as well as vocal cord pathology.
The degree of trismus depends on the extent of lateral pharyngeal space inflammation. If it is very marked, one should be concerned with the possibility of a lateral pharyngeal space cellulitis. The finding of tender ipsilateral cervical lymphadenopathy involving single or multiple nodes is not uncommon. The affected lymph nodes may be quite firm. In presentations with significant nodal inflammation, the patient may experience torticollis and limitation of neck mobility. A more detailed evaluation is essential if suspicion of an accompanying cervical abscess exists.
Indications
Indications for considering the diagnosis of a PTA include the following:
- Unilateral swelling of the peritonsillar area
- Unilateral swelling of the soft palate, with anterior displacement of the ipsilateral tonsil
- Nonresolution of acute tonsillitis, with persistent unilateral tonsillar enlargement
In adults, the clinical signs significantly associated with peritonsillar abscess include trismus, uvular deviation, and inferior displacement of the superior pole of the affected tonsil.3 In cases of PTA, when incision and drainage (I&D) is performed, it leads to immediate improvement of the patient's symptoms. Needle aspiration may be used as a diagnostic modality and as a therapeutic one, because it allows the accurate localization of the abscess cavity. The aspirated fluid may be sent for culture, and in some cases, an I&D may not be necessary. If patients continue to report recurring and/or chronic sore throats following proper I&D, a tonsillectomy may be indicated.
Relevant Anatomy
The palatine tonsils are paired lymphoid organs found between the palatoglossal and palatopharyngeal folds of the oropharynx. They are surrounded by a thin capsule that separates the tonsil from the superior and middle constrictor muscles.
The anterior and posterior pillars form the front and back limits of the peritonsillar space. Superiorly, this potential space is related to the torus tubarius, while inferiorly it is bounded by the pyriform sinus. Composed solely of loose connective tissue, a severe infection may rapidly result in pus formation. The inflammation and suppurative process may extend to involve the soft palate, the lateral wall of the pharynx, and, occasionally, the base of the tongue.
The tonsillar fossa has a rich network of lymphatic vessels leading to the parapharyngeal space and the upper cervical lymph nodes, which explains the pattern of adenopathy observed clinically. Ipsilateral upper cervical lymphadenopathy is the result of the spread of infection to the regional lymphatics. Occasionally, the severity of the suppurative process may lead to a cervical abscess, especially in very fulminant or rapidly progressive cases.
Contraindications
Intraoral drainage has a high rate of success and a low rate of recurrence and morbidity. Normally, unless the patient presents with recurrent tonsillitis or recurrent PTA, tonsillectomy is not indicated. However, in situations in which the abscess is located in an area difficult to access, a tonsillectomy may be the only way to drain the abscess.
More on Peritonsillar Abscess |
 Overview: Peritonsillar Abscess |
| Workup: Peritonsillar Abscess |
| Treatment: Peritonsillar Abscess |
| Follow-up: Peritonsillar Abscess |
| Multimedia: Peritonsillar Abscess |
| References |
| Further Reading |
| Next Page » |
References
Marom T, Cinamon U, Itskoviz D, et al. Changing trends of peritonsillar abscess. Am J Otolaryngol. Apr 22 2009;[Medline].
Repanos C, Mukherjee P, Alwahab Y. Role of microbiological studies in management of peritonsillar abscess. J Laryngol Otol. Aug 2009;123(8):877-9. [Medline].
Kilty SJ, Gaboury I. Clinical predictors of peritonsillar abscess in adults. J Otolaryngol Head Neck Surg. Apr 2008;37(2):165-8. [Medline].
Ramirez-Schrempp D, Dorfman DH, Baker WE, Liteplo AS. Ultrasound soft tissue applications in the pediatric emergency department: to drain or not to drain?. Pediatr Emerg Care. Jan 2009;25(1):44-8. [Medline].
Ozbek C, Aygenc E, Tuna EU, Selcuk A, Ozdem C. Use of steroids in the treatment of peritonsillar abscess. J Laryngol Otol. Jun 2004;118(6):439-42. [Medline].
Heidemann CH, Wallen M, Aakesson M, et al. Post-tonsillectomy hemorrhage: assessment of risk factors with special attention to introduction of coblation technique. Eur Arch Otorhinolaryngol. Jul 2009;266(7):1011-5. [Medline].
Apostolopoulos NJ, Nikolopoulos TP, Bairamis TN. Peritonsillar abscess in children. Is incision and drainage an effective management?. Int J Pediatr Otorhinolaryngol. Mar 1995;31(2-3):129-35. [Medline].
Bluestone CD. Current indications for tonsillectomy and adenoidectomy. Ann Otol Rhinol Laryngol Suppl. Jan 1992;155:58-64. [Medline].
Brook I. Anaerobic Infections in Childhood. Boston, Mass: G.K. Hall Medical Publisher; 1983:32.
Brook I, Frazier EH, Thompson DH. Aerobic and anaerobic microbiology of peritonsillar abscess. Laryngoscope. Mar 1991;101(3):289-92. [Medline].
Buckley AR, Moss EH, Blokmanis A. Diagnosis of peritonsillar abscess: value of intraoral sonography. AJR Am J Roentgenol. Apr 1994;162(4):961-4. [Medline].
Fairbanks DN. Pocket Guide to Antimicrobial Therapy in Otolaryngology--Head and Neck Surgery. American Academy of Otolaryngology--Head and Neck Surgery. Alexandria, Va: American Academy of Otolaryngology--Head and Neck Surgery; 1999:32-33.
Friedman NR, Mitchell RB, Pereira KD, Younis RT, Lazar RH. Peritonsillar abscess in early childhood. Presentation and management. Arch Otolaryngol Head Neck Surg. Jun 1997;123(6):630-2. [Medline].
Hanna BC, McMullan R, Hall SJ. Corticosteroids and peritonsillar abscess formation in infectious mononucleosis. J Laryngol Otol. Jun 2004;118(6):459-61. [Medline].
Kieff DA, Bhattacharyya N, Siegel NS, Salman SD. Selection of antibiotics after incision and drainage of peritonsillar abscesses. Otolaryngol Head Neck Surg. Jan 1999;120(1):57-61. [Medline].
Lyon M, Blaivas M. Intraoral ultrasound in the diagnosis and treatment of suspected peritonsillar abscess in the emergency department. Acad Emerg Med. Jan 2005;12(1):85-8. [Medline].
Snow DG, Campbell JB, Morgan DW. The microbiology of peritonsillar sepsis. J Laryngol Otol. Jul 1991;105(7):553-5. [Medline].
Strong EB, Woodward PJ, Johnson LP. Intraoral ultrasound evaluation of peritonsillar abscess. Laryngoscope. Aug 1995;105(8 Pt 1):779-82. [Medline].
Suskind DL, Park J, Piccirillo JF, Lusk RP, Muntz HR. Conscious sedation: a new approach for peritonsillar abscess drainage in the pediatric population. Arch Otolaryngol Head Neck Surg. Nov 1999;125(11):1197-200. [Medline].
Weinberg E, Brodsky L, Stanievich J, Volk M. Needle aspiration of peritonsillar abscess in children. Arch Otolaryngol Head Neck Surg. Feb 1993;119(2):169-72. [Medline].
Further Reading
Clinical guidelines:
Acute pharyngitis in children. Michigan Quality Improvement Consortium - Professional Association. 2004 Apr (revised 2009 Jan). 1 page. NGC:007052
Clinical trials:
Impact of Anti-inflammatory and Antibiotic Therapy on the Emergence of Peri-tonsillar Abscess (APA)
Keywords
peritonsillar abscess, tonsillitis, tonsillectomy, tonsil removal, trismus, peritonsillar, acute tonsillitis, chronic tonsillitis, pyriform sinus, tonsil abscess, torus tubarius
