Does all tonsillitis require antibiotics?

Antibiotic Treatment for Tonsillitis

Not all tonsillitis requires antibiotics. Only bacterial tonsillitis, specifically Group A Streptococcal (GAS) tonsillitis confirmed by rapid antigen detection test or throat culture, should be treated with antibiotics. 1, 2, 3

Diagnosis of Bacterial vs. Viral Tonsillitis

• Clinical features suggesting bacterial tonsillitis include fever >38°C, tonsillar exudates, anterior cervical lymphadenopathy, and absence of cough 4
• Features suggesting viral etiology include cough, rhinorrhea (runny nose), hoarseness, and oral ulcers 3
• Testing for Group A Streptococcus is recommended for patients with symptoms suggestive of streptococcal pharyngitis before initiating antibiotics 1
• The McIsaac scoring system can help guide clinical decision-making:
  • +1 point each for: Temperature ≥38°C, absence of cough, tender anterior cervical adenopathy, tonsillar swelling/exudate, age <15 years
  • -1 point for: Age ≥45 years
  • Score interpretation:
    • Score ≤1: Neither antibiotics nor culture required
    • Score 2-3: Take culture, base antibiotic decision on result
    • Score ≥4: Initiate antibiotics immediately or take culture 1

Antibiotic Treatment for Confirmed Bacterial Tonsillitis

• Penicillin V remains the first-line antibiotic treatment for confirmed GAS tonsillitis due to its proven efficacy, safety, narrow spectrum, and low cost 2
• Amoxicillin is an acceptable alternative first-line option 2
• For patients with penicillin allergy, alternatives include:
  • Cephalexin (avoid in immediate-type hypersensitivity to penicillin)
  • Clindamycin
  • Macrolides (azithromycin, clarithromycin) - note increasing resistance of GAS to macrolides 2, 5

Benefits and Limitations of Antibiotic Treatment

• For patients with confirmed GAS tonsillitis, antibiotics:
  • Shorten symptom duration by 1-2 days (modest benefit)
  • May prevent complications including acute rheumatic fever and peritonsillar abscess
  • Reduce contagiousness 1, 3
• The number needed to treat to reduce symptoms is 6 after 3 days of treatment and 21 after 1 week of treatment 1
• Despite susceptibility of GAS to penicillin, bacteriologic failure occurs in up to 20% of patients treated with penicillin 6
• Possible reasons for treatment failure include:
  • Beta-lactamase-producing bacteria "shielding" GAS
  • Poor compliance with 10-day treatment course
  • Bacterial interference
  • GAS intracellular internalization 6

Treatment Duration and Follow-up

• Standard treatment duration is 10 days for most antibiotics to ensure eradication of GAS and prevent complications 2
• The 10-day antibiotic therapy has proven effective in preventing rheumatic fever and glomerulonephritic diseases 7
• Shorter courses (5 days) with certain antibiotics like azithromycin may be effective due to prolonged tissue half-life 8

Management of Viral Tonsillitis

• Symptomatic treatment is recommended for viral tonsillitis:
  • Acetaminophen or NSAIDs for pain and fever control
  • Topical agents containing anesthetics may provide temporary relief
  • Warm salt water gargles for symptom relief 3
• Antibiotics provide no benefit for viral tonsillitis and contribute to antibiotic resistance 3

Special Considerations

• Chronic tonsillitis (recurrent episodes) may require different management approaches:
  • Consider tonsillectomy if ≥7 episodes in the past year, ≥5 episodes per year in the past 2 years, or ≥3 episodes per year in the past 3 years 4
  • Clindamycin may be effective in preventing recurrence of acute tonsillitis in patients with multiple episodes 9
• Tonsillectomy is not recommended solely to reduce the frequency of GAS pharyngitis without meeting established criteria 4

Common Pitfalls to Avoid

• Prescribing antibiotics without confirming GAS infection through diagnostic tests 1, 4
• Confusing GAS carrier state with recurrent bacterial infections 4
• Using aspirin in children with viral infections due to risk of Reye syndrome 3
• Overuse of corticosteroids for symptom relief 3

By following these evidence-based guidelines, clinicians can ensure appropriate management of tonsillitis, reducing unnecessary antibiotic use while effectively treating bacterial infections.