Introduction to croup

Croup (acute laryngotracheobronchitis) presents with:

• an acute viral prodrome
• hoarseness (or husky voice in those old enough to speak)
• stridor (a respiratory noise produced by turbulent airflow through the upper airways)
• a harsh barking ‘brassy’ cough
• variable airway obstruction due to inflammatory oedema within the subglottis.

It usually occurs in children aged 6 months to 6 years and lasts for 2 to 5 days; however, a postinfective cough may persist for many weeks. Parainfluenza viruses are the most common cause of croup; antibiotics are not indicated. See the NPS MedicineWise website for information on rational antibiotic use in children with respiratory tract infections.

Spasmodic croup refers to typical croup symptoms that occur without the acute viral prodrome, usually presenting at night. It usually has a shorter course, is often recurrent, and occurs in older children. Affected children often have coexisting asthma. Treatment is the same as for croup.