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Laryngotracheitis (croup) is a common cause of upper airway obstruction in children, with as many as 6% requiring hospitalization. It is most commonly caused by parainfluenza viruses 1 and 2, however, other etiologies include RSV, influenza, and adenovirus. Influenza A infection causes more severe infections. The incidence of disease is highest in the second year of life, but it is commonly seen between the ages of 1 and 6. Most cases occur in the fall and winter, but it may be seen throughout the year.

Acute laryngotracheitis usually presents with a 12-72 hour history of low grade fever and coryza. The patient subsequently develops hoarseness and a harsh/barking/seal-like cough. In moderate to severe cases the patient will have inspiratory stridor and retractions. Frequently, the respiratory distress is sudden in onset and is usually worse at night. Respiratory symptoms usually resolve over a 3-4 day period.

Differential Diagnosis

Spasmodic croup - this is very difficult to distinguish from laryngotracheitis. Affects children 3 months to 3 years and patients appear healthy overall other than a possible mild URI. The patient awakes suddenly at night with dyspnea, barking cough, and inspiratory stridor. Fever is not present and cool mist and gentle reassurance usually provide relief. Symptoms may resolve as quickly as they begin. This is thought to be a more allergic type of subglottic edema rather than infectious.

Bacterial Tracheitis - most commonly a complication of croup. Thus, patients most frequently have a preceding croup infection and then the patient develops high fever, toxicity and increasing respiratory distress. However, patient may also present suddenly without preceding croup. These cases are difficult to distinguish from epiglottitis, except that drooling is usually not present.

Epiglottitis - caused mainly by Haemophilus influenzae type b, therefore it is rarely encountered anymore. Patient is a previously healthy child who suddenly develops a sore throat and fever. Within hours patient appears toxic with drooling and hyperextension of the neck.

Other diagnoses to consider:
Foreign body, peritonsillar/retropharyngeal abscess, angioneurotic edema (usually facial swelling present as well), tracheal neoplasm/hemangioma/condyloma, vocal cord paralysis.

Croup Scoring System

StridorNoneOnly with agitationMild at restSevere
Air EntryNormalMild decreaseModerate decreaseMarked decrease
ColorNormalNot applicableNot applicableCyanotic
Mental StatusNormalRestless when
Restless when

Croup Severity

< or = 4MildOutpatient: mist, consider dexamethasone
5-6Mild to moderateDexamethasone, epinephrine, see admission criteria
7-8ModerateDexamethasone, epinephrine, admit
> or = 9SevereStabilize, dexamethasone, epinephrine, ICU

Tables taken from Fleisher, Gary and Ludwig, Stephen. Textbook of Pediatric Emergency Medicine. 2000. p. 746

Admission Criteria

  1. After receiving nebulized epinephrine, a patient may be observed in the ER for 2-3 hours or admitted. After the observation period the patient may be discharged to home if the child has:
    -no stridor at rest
    -normal air entry
    -normal color
    -normal level of consciousness
    -received one dose of 0.3-0.6 mg/kg dexamethasone IM, or 0.15-0.6mg/kg po
    -reliable transportation and caregivers
  2. The patient should be admitted if the child has:
    -hypoxia on room air
    -poor po intake
    -underlying laryngeal disease with exacerbation (e.g. subglottic stenosis)
    -respiratory failure
    -mild-moderate disease but lives a far distance from the hospital
    -caretakers who are unreliable
  3. A patient may be considered for admission who presents during the day, as croup typically worsens at night.

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