Acute Layngo-tracheo-bronchitis

Prodromal symptoms of upper respiratory tract infection preceding sings of respiratory tract obstruction is characteristic of croup.

Ref: Nelson 17th Edition, Page 1405;1406,14; Respiratory Care: Principles And Practice By Dean Hess, Neil MacIntyre, Shelley Mishoe, William Galvin, 2011, Page 1019.

Laryngotracheobronchitis is the most common infectious cause of airway obstruction in children, usually occurring between the ages of 6 months and 3 years. It is a viral infection most commonly caused by the parainfluenza virus, although numerous other organisms have been reported.

Ans. is ‘b’ i.e., The para influenza virus 

Croup (Laryngotracheobronchitis)

• Croup is a viral infection of upper respiratory tract.
• Children between the age of 1-5 years are affected.
• Para-influenza type I virus is the most common causative organism.
• Other viruses implicated in causaction are RSV, influenza virus, Adneovirus and Rhinovirus.

Ans. is ‘a’ i.e., Rhinoviruses

Croup (Laryngotracheobronchitis)

o Croup is a viral infection of upper respiratory tract.

o Children between the age of 1-5 years are affected.

Ans. is ‘b’ i.e., Laryngotracheobronchitis

This child has : –

i)           3 days history of upper respiratory tract infection.

ii)          Followed by stridor

These features suggest the diagnosis of croup.

Clinical manifestations of Croup

• Most patients have an upper respiratory tract infection with some combination of –
• Rhinorrhea               
• Pharyngitis
• Mild cough               
• Low grade fever

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

• Barking cough  
• Hoarseness  
• Inspiratory stridor

Ans. is `b’ i.e., Antibiotic

o Seal barking like croupy cough is a feature of laryngotracheobronchitis (Croup).

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

– Current Otolaryngology 2nd/ed p 472

Ans. is `d.’ i.e., Parainfluenza virus

Croup (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

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

• Gradual onset with a prodrome of upper respiratory symptoms
• Hoarseness and barking cough (croupy cough)
• Stridor (initially inspiratory than biphasic)
• 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)
• Imaging (X ray)
• Symmetric ‘steeple’ or ‘funnel shaped’ narrowing of the subglottic region (steeple sign)
• Hypopharyngeal widening or distension
• Normal epiglottis and aryepiglottic folds

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).
• Antibiotics are not routinely indicated in the treatment of Acute Laryngotracheobronchitis. Their use is limited if there is evidence of secondary bacterial infection.