Description

• Synonym(s): sore throat; tonsillitis; “strep throat”
• 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.

Epidemiology

• ~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% of cases)
• 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 a serious sequela, but is rare in the United States (<1 case 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.
• Affects all age groups; some etiologies and sequelae occur more frequently in 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 (associated with lower grade fever)
  • Rhinovirus; adenovirus (associated with conjunctivitis); parainfluenza virus; coxsackievirus (hand-foot-mouth disease); coronavirus; echovirus
  • Herpes simplex virus (HSV) (vesicular lesions); Epstein-Barr virus (EBV/mononucleosis); cytomegalovirus (CMV)
  • HIV
• Acute, bacterial (associated with 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

Genetics
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 (rheumatic fever possible, especially in children/adolescents 5 to 15 years)
• 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).