Pay close attention to your child’s next cough- it may suggest
a common but serious childhood condition known as croup. Experienced pediatricians can
recognize this particular cough in a crowded room; a sound often described
as a “seals bark” that carries a potentially deadly omen. The medical term for this condition is laryngotracheobronchitis- a complicated word for inflammation
of the upper respiratory tract, specifically the trachea and larynx.
Croup is most commonly caused by any one of several viral
infections, including parainfluenza, influenza (flu), rhinovirus (common cold),
adenovirus, respiratory syncitial virus (RSV), enterovirus and echovirus. In
about 20% of cases, bacterial infections such as Mycoplasma pneumoniae, Corynebacterium
diptheriae or staph or strep species are to blame.
The typical case of croup begins in a child under 6 years
old between the fall and early winter months: The child has a history of an
upper respiratory infection with fever and a cough that worsens at night. The child's breathing becomes
increasingly more labored, and a high pitched sound on inspiration known as
stridor develops. This characteristic barking cough may follow:
How does this happen? When the upper airways become inflamed
by an infection, swelling begins to narrow the passageway below the glottis
through which air travels. As the airway narrows, our bodies attempt to
compensate for poor airflow by increasing the respiratory rate (breaths per
minute). The result is rapid air exchange through a narrowed airway (stridor),
poor ventilation/oxygenation and respiratory distress.
It’s important that a pediatrician evaluates any child with
stridor. Though many cases are self limiting and resolve in less than 48 hours,
the doctor will rule out more serious conditions that present in a similar
fashion, particularly epiglottitis, bacterial tracheitis and aspiration of a
foreign budy. A simple oral dose of steroids (dexamethasone 0.15-0.60 mg/kg)
will rectify the child’s breathing difficulties, though moderate to severe
cases require inhaled (nebulized) racemic epinephrine.
- A diagnosis of epiglottitis is more likely when the child is experiencing excessive drooling and leaning over in a “sniffing position”.
- If the child is not treated, croup may lead to severe respiratory distress or become complicated with a pneumonia (known as laryngotracheobronciopneumonia)
- There are reports of repeated cases of croup, known as spasmodic croup, that may be caused by gastroesophageal reflux disease (GERD) or extreme sensitivity to the parainfluenza virus.
- Any time your child is suffering from an upper respiratory infection, he or she is at an increased risk for developing croup
References
Croup. Dynamed Database. Updated December 27, 2013. Accessed
June 2, 2014.
Petrocheilou A, Tanou K, Kalampouka E, Malakasioti G,
Giannios C, Kaditis AG. Viral croup: diagnosis and treatment algorithm. Pediatr
pulmonol. 2014; 49(5): 421-9.