What is the recommended treatment for a patient with a tonsillar abscess (peritonsillar abscess), considering their allergy status and severity of infection?

Treatment for Peritonsillar Abscess

The treatment of peritonsillar abscess requires immediate drainage (via needle aspiration, incision and drainage, or acute tonsillectomy) combined with antibiotic therapy effective against Group A Streptococcus and oral anaerobes, with penicillin-based regimens as first-line and clindamycin or cephalosporins for penicillin-allergic patients. 1, 2

Immediate Management: Drainage is Essential

All peritonsillar abscesses require drainage as the cornerstone of treatment. 1, 2 The three accepted surgical approaches are:

• Needle aspiration remains the gold standard for both diagnosis and treatment, particularly in the outpatient setting 2
• Incision and drainage for more extensive abscesses 3
• Acute tonsillectomy (quinsy tonsillectomy) for definitive treatment, which not only drains the abscess but eliminates potential for occult inferior pole or contralateral abscess 4

The choice depends on severity, patient cooperation, and clinician expertise. Most patients can be managed in the outpatient setting with needle aspiration. 1

Antibiotic Therapy

First-Line: Penicillin-Based Regimens

For patients without penicillin allergy, penicillin remains the drug of choice as Group A Streptococcus is an established pathogen in peritonsillar abscess. 5 However, peritonsillar abscesses are polymicrobial infections involving both aerobic and anaerobic bacteria. 1, 2

• Antibiotics must be effective against Group A Streptococcus AND oral anaerobes 1
• Appropriate options include penicillin, clindamycin, cephalosporins, or metronidazole 2

Penicillin-Allergic Patients

For penicillin-allergic patients, clindamycin is the preferred alternative because it provides excellent coverage against both Group A Streptococcus and anaerobes, including Fusobacterium necrophorum. 5, 3

• Clindamycin resistance among Group A Streptococcus is approximately 1% in the United States, making it a reasonable choice 5
• Fusobacterium necrophorum is recovered from 23-58% of peritonsillar abscess cases and is associated with significantly higher inflammatory markers 3
• Macrolides (erythromycin, clarithromycin, azithromycin) have 5-8% resistance rates and should be used cautiously 5

Cephalosporins are another option for penicillin-allergic patients (particularly those without type I hypersensitivity), as they achieve high tissue concentrations in inflamed peritonsillar tissue. 5, 4

• First-generation cephalosporins (cephalexin, cefadroxil) are preferred over broad-spectrum agents 5
• Cephalosporins should be avoided in patients with anaphylactic-type reactions to penicillin due to cross-reactivity risk 5

Adjunctive Therapy

Corticosteroids may be helpful in reducing symptoms and speeding recovery, though this is based on supportive evidence rather than definitive guidelines. 1

Supportive care includes:

• Adequate hydration 1
• Pain control with analgesics (acetaminophen or NSAIDs) 5
• Antipyretics for fever management 5

Special Considerations and Clinical Pitfalls

Modifying Factors for Tonsillectomy

History of more than one peritonsillar abscess is a modifying factor that favors tonsillectomy even in patients who don't meet standard criteria for recurrent throat infections. 5 This represents an important update from earlier guidelines that mentioned "history of peritonsillar abscess" without specifying the threshold.

Microbiology Considerations

Recent evidence shows Fusobacterium necrophorum is the most prevalent bacterial strain (23-58%) in peritonsillar abscess, more common than previously recognized. 3 This finding supports the use of clindamycin over macrolides in penicillin-allergic patients, as clindamycin has superior activity against Fusobacterium species.

Association with Parapharyngeal Abscess

52% of parapharyngeal abscess cases have concomitant peritonsillar abscess, which is much higher than previously documented. 3 This suggests that when peritonsillar abscess is present or suspected, combined tonsillectomy and intrapharyngeal incision should be considered to address both spaces.

Bacteremia Risk

Bacteremia occurs in 22% of patients during acute tonsillectomy for peritonsillar abscess, though interestingly, bacteremia during elective tonsillectomy is equally prevalent. 3 This challenges traditional distinctions about antibiotic prophylaxis requirements.

Common Pitfalls to Avoid

• Do not use tetracyclines, sulfonamides, or trimethoprim-sulfamethoxazole as they do not effectively eradicate Group A Streptococcus 5
• Avoid older fluoroquinolones (ciprofloxacin) which have limited activity against Group A Streptococcus 5
• Do not rely solely on antibiotics without drainage - the abscess must be drained for effective treatment 1, 2
• Recognize that smoking is associated with increased risk of peritonsillar abscess across all age groups, though this doesn't change acute management 3

When to Consider Immediate Tonsillectomy

Acute tonsillectomy should be considered in:

• Children, as it eliminates potential for occult inferior pole or contralateral abscess and spares future hospitalization 4
• Cases with suspected concomitant parapharyngeal involvement 3
• Patients with history of multiple peritonsillar abscesses 5
• Advanced cases not responding to needle aspiration 2