What is croup cough?

Croup Cough: Clinical Characteristics and Management

Croup cough is characterized by a distinctive barking or "seal-like" cough accompanied by inspiratory stridor, hoarseness, and varying degrees of respiratory distress, typically affecting children between 6 months and 6 years of age. 1, 2

Clinical Presentation

Characteristic Features

• Croup typically begins with upper respiratory infection symptoms including low-grade fever and coryza (runny nose), followed by the development of the characteristic barking cough 3
• The hallmark "barking seal" cough is distinctive and a key diagnostic feature 4
• Inspiratory stridor may be present, especially when the child is agitated or crying 1, 3
• Hoarseness is commonly present due to laryngeal inflammation 2

Timing and Progression

• Symptoms often worsen at night and may improve during the day 3
• In most children, symptoms subside quickly with resolution of the cough within two days 3
• Croup most commonly presents in late fall or early winter 1

Age Distribution

• Most commonly affects children between 6 months and 6 years of age 1, 2
• Recurrent croup (defined as two or more episodes per year) may indicate an underlying structural or inflammatory airway abnormality 5

Pathophysiology

• Croup involves inflammation and edema of the subglottic region of the larynx, trachea, and bronchi 5
• The narrowest part of a child's airway (subglottic region) becomes further narrowed by inflammation, leading to the characteristic symptoms 2
• Parainfluenza virus (types 1-3) is the most common causative agent 3
• Other viral causes include respiratory syncytial virus, influenza, and adenovirus 2

Differential Diagnosis

When evaluating a child with croup-like symptoms, it's important to consider other potentially serious conditions:

• Epiglottitis - characterized by rapid onset, toxic appearance, drooling, and inability to swallow 4
• Bacterial tracheitis - presents with high fever and toxic appearance 3
• Foreign body aspiration - sudden onset without prodromal symptoms 3
• Peritonsillar or retropharyngeal abscess - progressive dysphagia and neck pain 3
• Angioedema - may have associated urticaria or history of allergies 3

Management

Pharmacological Treatment

• A single dose of dexamethasone (0.15 to 0.60 mg/kg) is recommended for ALL patients with croup, including those with mild disease 3
• Oral administration is preferred, but intramuscular dexamethasone or nebulized budesonide are reasonable alternatives for children who cannot tolerate oral medication 2
• Nebulized epinephrine (racemic epinephrine) should be reserved for moderate to severe croup with significant respiratory distress 2, 3
• Children who receive nebulized epinephrine must be monitored for at least 2 hours after administration due to risk of rebound airway obstruction 1

Supportive Care

• Maintaining at least 50% relative humidity in the child's room is recommended, although evidence for humidification therapy is limited 1, 3
• Supplemental oxygen should be provided if there is evidence of hypoxemia 1
• Keep the child calm, as agitation can worsen symptoms 4

Indications for Hospital Admission

• Stridor at rest 4
• Evidence of exhaustion or respiratory distress 4
• Toxic appearance 4
• Inability to maintain adequate oral hydration 3
• Inadequate response to initial treatment 2

Prognosis

• Most cases of croup are mild and self-limiting 3
• Only 1-8% of patients with croup require hospital admission 3
• Less than 3% of admitted patients require intubation 3
• The cough typically resolves within 2 days in most children 3

Special Considerations

• Recurrent croup (≥2 episodes per year) warrants evaluation for underlying structural abnormalities or other conditions 5
• Simultaneous administration of corticosteroids and epinephrine reduces the rate of intubation in patients with severe croup and impending respiratory failure 2
• Early intervention with corticosteroids can reduce symptom severity and decrease rates of return visits, emergency department visits, and hospital admissions 2