Definition And Epidemiology

  • Inflammation involves epiglottis and adjacent supraglottic structures.
  • Progresses rapidly to life-threatening airway obstruction without prompt treatment.
  • Annual incidence decreased significantly post-vaccine implementation.
  • Current incidence rests at two cases per 10 million populations.
  • Prevalence shifted from preschool demographic to school-age children and adolescents.

Etiology

  • Primarily infectious origin.
  • Accidental ingestion of hot liquid can also cause supraglottic injury mimicking epiglottitis.
StatusBacterial PathogensViral Pathogens
ImmunocompetentHaemophilus influenzae type b (unvaccinated/incompletely immunized)Influenza Type A And B
Staphylococcus aureusParainfluenza Virus
Streptococcus pneumoniaeHerpes Simplex Virus
Streptococcus pyogenesEpstein-Barr Virus
Neisseria meningitidisHuman Immunodeficiency Virus
Pasteurella multocidaSevere Acute Respiratory Syndrome Coronavirus 2
ImmunocompromisedPseudomonas aeruginosaFungal Agents

Pathogenesis And Pathophysiology

  • Inflammatory edema accumulates in potential space between loosely attached squamous epithelial layer and epiglottal cartilage.
  • Swelling progresses with extreme rapidity.
  • Reduced upper airway caliber causes turbulent airflow.
  • Posterior and inferior curling of epiglottis creates ball-valve obstruction mechanism.

Clinical Features

Young Children

  • Acute, rapidly progressive, potentially fulminating course.
  • High fever, sore throat, severe dyspnea.
  • Toxic appearance within hours.
  • Marked dysphagia, labored breathing.
  • Drooling heavily present.
  • Stridor indicates near-complete airway obstruction.
  • Barking cough characteristically absent.
  • Classic tripod or sniffing posture adopted.
  • Patient sits upright, leans forward, chin thrust forward, neck hyperextended, mouth open.
  • Extreme reluctance to lie flat.
  • Brief air hunger and restlessness precede rapidly increasing cyanosis and coma.

Older Children And Adolescents

  • Low-grade fever accompanies progressively painful sore throat.
  • Severe sore throat out of proportion to oropharyngeal examination findings.
  • Severe dysphagia and drooling manifest.
  • Minimal respiratory distress initially.

Differential Diagnosis

  • Distinguishing acute upper airway obstruction etiologies remains critical.
FeatureAcute EpiglottitisViral CroupBacterial TracheitisRetropharyngeal Abscess
Age3–14 Years6 Months To 3 Years6 Months To 14 Years2–4 Years
Onset SpeedVery Rapid (Hours)GradualRapidGradual
AppearanceToxicNon-ToxicToxicToxic
FeverHigh GradeLow GradeHigh GradeHigh Grade
CoughAbsentBarkingBarking, Painful, ProductiveAbsent
Sore ThroatPresentAbsentAbsentPresent
Dysphagia/DroolingPresentAbsentAbsentPresent
Voice QualityMuffledHoarseVery HoarseMuffled
Neck Pain/StiffnessAbsentAbsentAbsentPresent
Tracheal TendernessAbsentAbsentPresentAbsent
Preferred PositionTripod, Extended NeckNo PreferenceSupineNo Preference
Lateral Neck RadiographThumb SignNormalSubglottic HazinessEnlarged Prevertebral Space
Adrenaline ResponseNoneVery GoodMinimal/NoneNone

Diagnostic Evaluation

Airway Precautions

  • Avoid invasive procedures prior to securing airway.
  • Withhold phlebotomy, intravenous line placement, or frightening interventions.
  • Forbid direct examination of oral cavity, pharynx, or larynx.
  • Agitation induced by pain worsens respiratory distress, precipitating sudden respiratory arrest.

Direct Visualization

  • Confirms diagnosis via direct laryngoscopy.
  • Reveals large, cherry red, swollen epiglottis.
  • Perform exclusively in controlled settings (Operating Room, Intensive Care Unit).
  • Require presence of airway experts (Anesthesiologist, Otolaryngologist).

Imaging

  • Soft-tissue lateral neck radiograph supports diagnosis if presentation remains atypical.
  • Reveals “Thumb Sign” representing enlarged epiglottis protruding from anterior hypopharyngeal wall.
  • Shows thickened aryepiglottic folds.
  • Demonstrates loss of vallecular air space.
  • Displays distended hypopharynx.
  • Ensure proper patient positioning with adequate hyperextension.
  • Never delay definitive airway management for imaging.

Laboratory Studies

  • Perform solely after airway stabilization.
  • Complete Blood Count shows elevated white blood cell count (non-specific finding).
  • Blood and epiglottic surface cultures yield variable results.
  • Concomitant bacteremia frequently present.

Management

Airway Control

  • Constitutes absolute mainstay of treatment.
  • Immediate endotracheal intubation, nasotracheal intubation, or tracheostomy indicated regardless of apparent distress level.
  • Select tube size 0.5 To 1.0 Millimeters smaller than standard age/height estimation.
  • Provide supplemental oxygen continuously in non-threatening manner.
  • Keep emergency surgical airway equipment readily available.
  • Extubation planned after 2 To 3 days following antimicrobial therapy initiation.
  • Confirm resolution of epiglottic swelling via fiberoptic laryngoscopy prior to extubation.

Pharmacotherapy

  • Administer appropriate antimicrobials immediately post-airway stabilization.
  • Ceftriaxone 50 Milligrams/Kilogram/Day Intravenous or Intramuscular once daily.
  • Alternatively, Cefotaxime 50 Milligrams/Kilogram/Dose Eight hourly.
  • Add Vancomycin 15 Milligrams/Kilogram/Day divided Eight hourly if Staphylococcus aureus suspected.
  • Continue antibiotics for 7 To 10 days.
  • Avoid Corticosteroids; unproven benefit.
  • Avoid Bronchodilators and Racemic Epinephrine; strictly ineffective.

Complications And Prognosis

  • Mortality rate reaches 6 Percent without artificial airway.
  • Mortality falls below 1 Percent following successful airway securement.
  • Fatal outcomes stem directly from complete laryngeal obstruction.
  • Concomitant infections include pneumonia, cervical adenopathy, and otitis media.
  • Meningitis and septic arthritis rarely occur alongside Haemophilus influenzae type b infections.
  • Pulmonary edema may associate with acute airway obstruction.

Prevention And Chemoprophylaxis

  • Maintain strict adherence to Haemophilus influenzae type b immunization schedules.
  • Initiate chemoprophylaxis swiftly for close contacts if vulnerable individuals reside in household.
  • Vulnerable contacts include infants below 12 months, incompletely vaccinated children below 4 years, and immunocompromised patients.
  • First-line prophylaxis: Rifampicin 20 Milligrams/Kilogram (Maximum 600 Milligrams) once daily for 4 days.
  • Rifampicin for infants below 3 months: 10 Milligrams/Kilogram once daily for 4 days.
  • Alternative options include Ceftriaxone Intravenous/Intramuscular for 2 days or Azithromycin once daily for 3 days.