Croup

Background

• Croup is a common childhood respiratory illness characterized by a barking cough and often accompanied by inspiratory stridor, hoarseness, and respiratory distress.
• Croup primarily affects children between the ages of 6 and 36 months, and occurs most commonly in the fall and early winter.
• Parainfluenza virus is the most common cause of croup.

Evaluation

• A clinical diagnosis based on history, physical exam, and treatment response is usually sufficient.
  • Suspect croup in a child with abrupt onset of a seal-like, barking cough, especially with symptom onset or worsening at night.
  • Assess for atypical findings (for example, wheezing, drooling, or toxic appearance) to help exclude alternative diagnoses.
  • Improved respiratory symptoms after treatment with corticosteroids, with or without nebulized epinephrine, supports diagnosis.
• Consider testing in children with atypical presentation or poor response to treatment, for example:
  • complete blood count with differential if bacterial infection suspected
  • anterior-posterior and lateral neck x-ray to help differentiate croup from other conditions (subglottic narrowing ["steeple sign"] suggests croup)
  • additional imaging to identify complications or other causes of airway obstruction
  • testing for bacterial or viral pathogens
• Consider laryngoscopy and bronchoscopy to detect airway abnormalities in patients with recurrent croup.

Management

• Corticosteroids are usually indicated for children with croup.
• Single-dose dexamethasone is the preferred first-line treatment. (Usual dose is 0.6 mg/kg orally or intramuscularly.)
• Give nebulized epinephrine in addition to corticosteroids to children with severe respiratory symptoms:
  • dose is 0.05 mL/kg of 2.25% racemic epinephrine (maximum 0.5 mL) or 0.5 mL/kg of 1:1,000 L-epinephrine (maximum 5 mL)
  • observe for ≥ 2 hours after administration because symptoms may recur as epinephrine wears off
• Oxygen with or without intubation may be indicated for respiratory compromise.
• Also consider:
  • neuraminidase inhibitor for severe croup due to influenza A or B, or during documented influenza epidemic
  • surgery for recurrent croup due to anatomic abnormality
• Disposition:
  • Admit to a hospital if moderate or severe respiratory symptoms are present ≥ 4 hours after a corticosteroid dose.
  • Discharge considerations:
    • For children with mild croup at presentation, an observation period is not necessary.
    • For children with moderate croup at presentation, consider a discharge following corticosteroid treatment if only mild symptoms persist after 1-4 hours of observation.
    • For children with severe croup at presentation, consider a discharge if only mild symptoms persist ≥ 2 hours after the last epinephrine dose.