Epidemiology

Etiology

• Acute tonsillopharyngitis
  • Viral (50–80% of cases): adenovirus, EBV, CMV, HSV, rhinovirus, coronavirus, influenza and parainfluenza viruses, HIV
    • Viral pharyngitis is more common than bacterial pharyngitis in both adults (up to 90% of cases) and children (up to 40% of cases).
  • Bacterial (15–30% of cases)
    • Most common: acute GAS tonsillopharyngitis caused by Streptococcus pyogenes, also known as Group A Streptococcus (GAS)
    • Others: Neisseria gonorrhoeae, Corynebacterium diphtheriae

Pathophysiology

Clinical features

Acute bacterial tonsillopharyngitis

• Sudden onset of symptoms: fever, sore throat, dysphagia
• Significantly inflamed pharynx
  • Pharyngeal and/or tonsillar erythema and edema
  • Pharyngeal and/or tonsillar exudates (rare in children < 3 years of age)
    • Fibrin deposits appear as white spots on the tonsils (杨梅舌).
    • See Gray-white exudates of throat
  • Palatal petechiae
• Cervical lymphadenitis
• Absence of cough

Acute viral tonsillopharyngitis

Accompanied by symptoms of a common cold (rhinitis and/or pharyngitis)

Diagnostics

Rapid strep test

• Modality: rapid antigen detection test (RADT) specific for GAS antigens.
• Indications: first-line test in suspected acute bacterial tonsillopharyngitis
  • All symptomatic children ≥ 3 years of age and adults (unless symptoms are suggestive of acute viral tonsillopharyngitis)
• Procedure: Swab the patient's tonsils and the back of the throat.
• Findings
  • Identifies the presence of GAS (positive RADT).
  • Time to result: 5–10 minutes

Additional laboratory tests

• Antistreptolysin O (ASO) titer
  • Elevated levels suggest a previous GAS infection; not helpful to diagnose acute pharyngitis
  • Indicated in the workup of nonsuppurative complications of GAS tonsillopharyngitis (e.g., acute rheumatic fever, PSGN).

Treatment