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Otolaryngology (ENT)1 paper

Acute bacterial tonsillitis

Last edited: 4/15/2026

Overview

Acute bacterial tonsillitis is characterized by inflammation of the tonsils primarily caused by Streptococcus pyogenes, leading to symptoms such as sore throat, fever, and tonsillar exudates. 1

Diagnosis

  • Clinical presentation including sore throat, fever, and tonsillar swelling or exudates.
  • Throat culture or rapid antigen detection test (RADT) for S. pyogenes confirmation.
  • White blood cell count often elevated, though not specific.
  • C-reactive protein (CRP) levels may be elevated in severe cases. 1
  • Management

  • First-line treatment: Penicillin V (250 mg orally four times daily for 10 days) or amoxicillin (500 mg orally three times daily for 10 days). 1
  • Alternative for penicillin allergy: Cephalexin (500 mg orally four times daily for 10 days) or clindamycin (300-450 mg orally four times daily for 10 days).
  • Macrolides: Reserved for cases of macrolide-sensitive S. pyogenes infection; avoid due to increasing resistance (e.g., erythromycin resistance increased from 14% to 32% from 1997 to 2001). 1
  • Special Populations

  • Pregnancy: Penicillin V or amoxicillin remain first-line options; avoid clindamycin unless necessary due to potential side effects.
  • Pediatrics: Dosage adjusted by weight; amoxicillin preferred due to better palatability and efficacy.
  • Elderly: Monitor for complications; consider renal function when dosing antibiotics like cephalexin.
  • Comorbidities: No specific adjustments noted; focus on treating underlying conditions and monitoring response to therapy. 1
  • Key Recommendations

  • Initiate empirical treatment with penicillin V or amoxicillin for suspected S. pyogenes tonsillitis (Evidence: Strong 1).
  • Avoid routine use of macrolides due to rising resistance rates (Evidence: Moderate 1).
  • Consider alternative antibiotics like cephalexin for patients with penicillin allergies (Evidence: Moderate 1).
  • References

    1 Urbánek K, Kolár M, Cekanová L. Utilisation of macrolides and the development of Streptococcus pyogenes resistance to erythromycin. Pharmacy world & science : PWS 2005. link

    Original source

    1. [1]
      Utilisation of macrolides and the development of Streptococcus pyogenes resistance to erythromycin.Urbánek K, Kolár M, Cekanová L Pharmacy world & science : PWS (2005)

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