Acute Layngo-tracheo-bronchitis

ACUTE LARYNGOTRACHEOBRONCHITIS

• Laryngotracheobronchitis is the most common infectious cause of obstruction in children usually occurring between the ages of 6 months and 3 years.
• Male children (boys) are characteristically more frequently involved than females (girls).

Etiology:

• It is a viral infection most frequently caused by Parainfluenza virus.
• Other viruses implicated in causaction are RSV, influenza virus, Adneovirus,Coxsackie A and B virus, Rhinovirus.

Pathology:

• The most characteristic pathological feature is edema formation in the subglottic area
• The loose areolar tissue in the subglottic area swells up and causes predominant signs of upper airway obstruction.

Presentation:

Most patients have an upper respiratory tract infection with some combination of –

• Rhinorrhea               
• Pharyngitis
• Mild cough               
• Low grade fever

 After 1-3 days signs and symptoms of upper respiratory tract obstruction become apparent –

• Barking cough 

Seal barking like croupy cough is a feature of laryngotracheobronchitis  

• Hoarseness  
• Stridor (initially inspiratory than biphasic)

Stridor decreases on lying down.

• Fever is usually low grade (or absent) although may occasionally be high grade.
• Droolings is characteristically absent and there is no dysphagia (seen in epiglottitis)

Diagnosis:

• Chest X-ray in croup (Laryngotracheobronchitis) reveals a characteristic narrowing of the subglottic region called steeple sign.

Treatment:

• Mild symptoms (barking cough but no stridor at rest)
• Supportive therapy alone with humified oxygen, oral hydration and minimal handling.
• Moderate symptoms (barking cough with stridor at rest)
• Active intervention with humified oxygen, Nebulized racemic epinephrine and glucocorticoids (steroids).
• Severe symptoms (impending respiratory failure)
• Require an artificial airway (Intubation with endotracheal tube or tracheostomy may be required).
• Broncoscopy may be required to suck out viscid tracheobronchial secretions.
• Antibiotics are not routinely indicated in the treatment of Acute Laryngotracheobronchitis. Their use is limited if there is evidence of secondary bacterial infection.