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Croup and stridor in children
Acute stridor in a child is usually viral croup — barking cough, hoarseness and stridor at night — treated with dexamethasone and, in moderate-to-severe cases, nebulised epinephrine; a toxic, drooling child points to more dangerous diagnoses.
Why it matters in the exam
The exam presents a two-year-old with a "seal-like" cough and asks for the treatment: a single dose of dexamethasone for every child with croup, even mild, and nebulised epinephrine when there is stridor at rest, with observation afterwards. The differential question tests whether the conditions that are not croup can be recognised: epiglottitis, bacterial tracheitis, a foreign body and a retropharyngeal abscess.
In an infant with chronic stridor from birth the common diagnosis is laryngomalacia: worse lying on the back and during feeds, better lying prone, and most cases resolve by 18 months. A foreign body has a history of sudden choking and one-sided findings; a normal X-ray does not exclude it, and the treatment is rigid bronchoscopy.
Severity is judged by stridor at rest, recessions, level of consciousness and cyanosis; a normal oxygen saturation does not guarantee that the obstruction is mild. A child who received epinephrine and remains free of stridor at rest at the end of observation can usually go home with advice.
Key points
- Croup: parainfluenza, age 6 months to 3 years, barking cough and stridor.
- A single dose of dexamethasone for all croup; nebulised epinephrine for stridor at rest.
- Epiglottitis: toxic, drooling, tripod, no barking cough — airway in the operating theatre.
- Bacterial tracheitis: croup that worsens with high fever and does not respond to epinephrine.
- Laryngomalacia is the common cause of chronic stridor in an infant.
Summary table
| Condition | Clinical picture | Typical finding | Treatment |
|---|---|---|---|
| Croup (parainfluenza) | Age 6 months to 3 years, coryza, barking cough, stridor at night | "Steeple sign" on X-ray — not needed for the diagnosis | Dexamethasone 0.15–0.6 mg/kg orally as a single dose; nebulised epinephrine for stridor at rest |
| Epiglottitis | High fever, toxic, drooling, tripod position, no barking cough | "Thumb sign" on a lateral X-ray | Do not upset the child or examine the throat; airway in the operating theatre; ceftriaxone |
| Bacterial tracheitis | Looks like croup, then worsens, high fever, toxic | No response to epinephrine; thick tracheal secretions | Airway and antibiotics covering S. aureus |
| Foreign body | Sudden choking while eating or playing | One-sided wheeze, unilateral hyperinflation on an expiratory film | Rigid bronchoscopy |
| Laryngomalacia | Stridor from a few weeks of age, worse supine and with feeds | Thriving infant in most cases | Observation; surgery only for faltering growth or distress |
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Sources
- Canadian Paediatric Society position statement: Acute management of croup in the emergency department, 2017, reaffirmed — Corticosteroids and nebulised epinephrine
- Nelson Textbook of Pediatrics, 22nd edition (2024) — Acute Inflammatory Upper Airway Obstruction (Croup, Epiglottitis, Laryngitis, and Bacterial Tracheitis)
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.