DESCRIPTION

The epiglottis is a cartilaginous tissue at the back of the throat that protects the airway during swallowing. The epiglottis can become infected leading to swelling and if untreated can cause airway obstruction, respiratory failure, and death. Epiglottitis can rapidly progress; fast recognition and treatment is imperative.

EPIDEMIOLOGY

• Mode of transmission is by inhalation of respiratory tract droplets or contact with respiratory tract secretions.
• Year-round occurrence
• All geographic areas
• Can have secondary cases in households or child care centers
• May be more frequent in children with immunodeficiency, under vaccinated status, or requiring frequent antibiotics
• Impact of vaccinations
  • Prior to 1990, Haemophilus influenzae type b caused up to 90% of reported epiglottitis cases occurring in children between the ages of 1 and 4 years.
  • After the introduction of the conjugate vaccines in 1987 (approved for use at 15 months) and 1990 (approved for use at 2, 4, and 6 months), 90–95% of cases occur in adults and no causative organism is found.
• Incidence
  • Pediatric epiglottitis due to any organism has declined in the postvaccine era (0.02 to 0.6/100,000 per year from 3 to 6/100,000 per year).
  • Adult cases have remained steady (1 to 4/100,000 per year).

ETIOLOGY

• H. influenzae, nontypeable and type b (type b accounted for up to 90% of cases prior to the introduction of H. influenzae type b vaccine)
• Streptococcus pneumoniae
• Streptococcus pyogenes (group A β-hemolytic Streptococcus)
• Staphylococcus aureus
• Groups C and G β-hemolytic Streptococcus
• Candida albicans may be an etiologic agent in immunocompromised patients and those receiving prolonged corticosteroid treatment.
• Pasteurella multocida has been implicated in a few cases after exposure to nasopharyngeal secretions from a cat.
• Other rare isolates: Moraxella catarrhalis, Klebsiella pneumoniae, Neisseria meningitidis, Pseudomonas species, Histoplasma
• Bacterial superinfection of viral infections including herpes simplex, parainfluenza, varicella, Epstein-Barr
• Varicella can cause primary infection or lead to a secondary infection, often with S. pyogenes.
• Noninfectious etiologies include thermal injuries, trauma, and caustic ingestions.

GENERAL PREVENTION

• Universal immunization with H. influenzae type b capsular polysaccharide conjugate vaccines at 2 and 4 months (potential dose at 6 months, depending on the vaccine), with booster at 12 to 15 months
• Control measures:
  • Prophylaxis for H. influenzae type b index case is considered if the household or child care center contains children <4 years old who are unvaccinated or incompletely vaccinated.
  • Rifampin: 20 mg/kg/24 h PO (max 600 mg/24 h), once daily for 4 days

PATHOPHYSIOLOGY

• Edema of the supraglottic structures (uvula, aryepiglottic folds, arytenoids, epiglottis, and vocal cords) reduces the airway aperture.
• Respiratory arrest can be caused by airway obstruction, aspiration of oropharyngeal secretions, or mucus plugging.