laryngotrakeobronkit

Laryngotracheobronchitis, sometimes spelled laryngotrakeobronkit, is an acute inflammatory condition of the larynx, trachea, and bronchi. The illness is most common in young children and is typically known as croup. It often follows a viral infection and results in swelling of the subglottic airway, which can cause varying degrees of airway obstruction.

The condition is usually caused by viral agents, with parainfluenza viruses being the most frequent culprits. Less commonly, influenza, respiratory syncytial virus, and other pathogens may be involved. It mainly affects children between 6 months and 3 years, though older children and adults can be affected.

Pathophysiologically, inflammation and edema in the laryngeal and subglottic regions lead to a narrowing of the upper airway. This produces a characteristic barking cough, hoarseness, and inspiratory stridor. Retractions and tachypnea may accompany respiratory distress in more severe cases.

Diagnosis is primarily clinical, based on history and examination. A chest radiograph may be performed if the diagnosis is uncertain and can show subglottic narrowing in some cases, sometimes called the steeple sign. Differential diagnoses include epiglottitis, bacterial tracheitis, and foreign body aspiration.

Management depends on severity. Mild cases may be managed with supportive care and a single dose of dexamethasone (oral or intramuscular). Moderate to severe disease may require dexamethasone plus nebulized epinephrine in an emergency setting, humidified oxygen if hypoxemic, and close observation. Antibiotics are not routinely used unless bacterial infection is suspected. Most cases resolve within 3–7 days, though symptoms can persist longer. Severe airway obstruction is rare but requires prompt evaluation and, if needed, airway support.