Croup

Snapshot

A 4-year-old boy presents to the emergency room for a cough. His mom reports that he has had this cough for about a day along with fevers, runny nose, and a hoarse voice. He started having some difficulty breathing this afternoon, so his mother brought him to the emergency room. On physical exam, he has a deep barking cough, use of accessory muscles, and inspiratory stridor. He is sent for a chest radiograph, which showed a positive steeple sign. He is immediately given nebulized epinephrine and a dose of steroids. The physician reassures the patient’s mother that this will likely resolve without any complications.

Introduction

Clinical definition
- upper respiratory infection characterized by barking cough
Epidemiology
- incidence
  - common
- demographics
  - children < 6 years of age
  - boys > girls
Etiology
- parainfluenza virus (most common)
  - paramyxovirus
    - RNA virus
- influenza virus
  - orthomyxovirus
    - RNA virus
Pathogenesis
- the virus causes inflammation of the upper airway
  - edema, epithelial necrosis, and infiltration of inflammatory cells
  - this causes narrowing of subglottic airway, resulting in stridor and increased work of breath
Associated conditions
- bronchiolitis
Prognosis
most cases resolve without complications

Presentation

Imaging

Studies

Differential

Acute epiglottitis
- distinguishing factors
  - patients typically have muffled voice, drooling, high fever, and have dysphagia
  - a medical emergency
absence of barking cough

Treatment

Complications