Pharyngitis is a topic covered in the 5-Minute Clinical Consult.

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  • Acute or chronic inflammation of the pharyngeal mucosa and underlying structures of the throat
  • Group A Streptococcus (GAS) pharyngitis is notable for preventable suppurative (e.g., retropharyngeal or peritonsillar abscess) and nonsuppurative (e.g., rheumatic sequelae) complications.
  • Synonym(s): sore throat; tonsillitis; “strep throat”


  • ~15 million cases are diagnosed yearly.
  • Accounts for 1–2% of all outpatient visits and 6% of all pediatric visits to primary care physicians
  • Most commonly viral (40–60%)
  • GAS is the most common bacterial cause of acute pharyngitis, accounting for 15–30% of pediatric and 5–15% of adult cases. The incubation period ranges from 24 to 72 hours.
  • Rheumatic fever is rare in the United States (<1 per 100,000). Early antibiotic use has diminished occurrence.
  • 3,000 to 4,000 patients with group A β-hemolytic streptococcal infection must be treated to prevent one case of acute rheumatic fever.
  • All age groups, some etiologies more common with certain age groups

Pediatric Considerations
The highest incidence of rheumatic fever is in children 5 to 18 years as a rare sequela of streptococcal pharyngitis.

Etiology and Pathophysiology

  • Acute, viral (lower grade fever)
    • Rhinovirus
    • Adenovirus (associated with conjunctivitis)
    • Parainfluenza virus
    • Coxsackievirus (hand-foot-mouth disease)
    • Coronavirus
    • Echovirus
    • Herpes simplex virus (vesicular lesions)
    • Epstein-Barr virus (EBV/mononucleosis)
    • Cytomegalovirus (CMV)
    • HIV
  • Acute, bacterial (higher fevers)
    • Group A β-hemolytic streptococcus
    • Neisseria gonorrhoeae
    • Corynebacterium diphtheriae (diphtheria)
    • Haemophilus influenzae
    • Moraxella catarrhalis
    • Chlamydia pneumonia
    • Fusobacterium necrophorum (20% young adult cases)
    • Group C or G streptococcus
    • Arcanobacterium haemolyticum
    • Mycoplasma pneumoniae
    • Francisella tularensis (tularemia)
  • Acute, noninfectious
    • Various caustic, mechanical, or trauma-related (including endotracheal intubation)
  • Chronic
    • More likely noninfectious
    • Chemical irritation (GERD)
    • Smoking
    • Neoplasms
    • Vasculitis
    • Radiation changes

Patients with a family history of rheumatic fever have a higher risk of rheumatic sequelae following an untreated group A β-hemolytic streptococcal infection.

Risk Factors

  • Epidemics of group A β-hemolytic streptococcal disease
  • Cold and flu season (late fall through early spring)
  • Age (especially children/adolescents 5 to 15 years)
  • Family history of rheumatic fever
  • Close contact with infected individuals (home, daycare, military barracks)
  • Immunosuppression
  • Smoking/secondhand smoke exposure
  • Acid reflux
  • Oral sex
  • Diabetes mellitus
  • Recent illness (secondary postviral bacterial infection)
  • Chronic colonization of bacteria in tonsils/adenoids

General Prevention

  • Avoid close contact with infectious patients.
  • Wash hands frequently.
  • Avoid first or secondhand smoke.
  • Manage preventable causes (e.g., GERD).

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