Croup is a group of respiratory diseases that often affects infants and children under age 6. The group of respiratory diseases consists of
spasmotic croup acute laryngotracheitis laryngotracheobronchitis (LTB) laryngotracheobronchopneumitis (LTBP) laryngeal diptheria.
The infection may extend from the vocal cords (larynx) to the trachea and bronchi. This infection results in inflammation and increased mucus production. 5-10% of children with croup will require admission to the hospital.
Children between the ages of 6 months and 3 years are most likely to get croup. This common viral illness is estimated to occur in 5% of children between the ages of 1-2 years Croup is rarely seen in adults because their larger breathing passages (trachea and larynx) can accommodate the inflammation without producing symptoms.
Croup is characterized by
Harsh "barking" cough and sneeze Inspiratory stridor (a high-pitched sound heard on inhalation) Nausea/vomiting Fever Hoarseness Severe cases will have respiratory distress
The "barking" cough (often described as a "seal like bark") of croup is diagnostic. Stridor will be provoked or worsened by agitation or crying. If stridor is also heard when the child is calm, critical narrowing of the airway may be imminent.
In diagnosing croup, it is important for the physician to consider and exclude other causes of shortness of breath and stridor, such as foreign body aspiration and epiglottitis.
The pictures to the right show the area involved in croup. The x-ray on the left shows the narrowing in the trachea, also called the "steeple sign." The picture on the right shows the narrowed trachea (subglottic area).
Croup is a viral respiratory infection that is easily passed among children. Common causes include
Parainfluenza (primarily types 1 and 2 ) Influenza Adenovirus Respiratory syncytial virus (RSV) Rhinovirus Measles
The Modified Westley Clinical Scoring System for Croup
Inspiratory stridor: Not present – 0 points When agitated/active – 1 point At rest – 2 points Intercostal recession: Mild – 1 point Moderate – 2 points Severe – 3 points Air entry: Normal – 0 points Mildly decreased – 1 point Severely decreased – 2 points Cyanosis: None – 0 points With agitation/activity – 4 points At rest – 5 points Level of consciousness: Normal – 0 points Altered – 5 points Possible Score 0–17: <4=mild croup, 4–6=moderate croup, >6=severe croup.
Epiglottitis Inhaled foreign body Inhaled noxious substance Acute anaphylaxis Bacterial tracheitis Diphtheria Laryngomalacia or other congenital cause of upper airway stenosis (e.g. aortic arch abnormality causing external airway compression) Peritonsillar abscess (quinsy) Retropharyngeal abscess Angioneurotic oedema Laryngeal mucosal lesions such as laryngeal web, papillomata and haemangioma Vocal cord paralysis
Exams and Tests
A pulse oximeter may be used to determine if the child is getting an adequate amount of oxygen. This is a skin sensor, placed on the finger, toe, or ear, connected to an oximeter machine by a wire. Normal levels would be above 96% on room air. X-rays of the neck may be ordered to differentiate croup from epiglottitis, which is a more serious condition. Children with croup typically have visible upper airway narrowing, called a steeple sign, that can be seen on x-rays.
Blood tests are usually not necessary.
Croup Treatment at Home
Breathing moist air from steamed water, a hot shower, or a coolmist humidifier is helpful in the majority of cases. Coughing and stridor should improve within 20-30 minutes. Taking the child outside while dressed warmly on a cold day for a few minutes may be helpful as well. The cool moist air that the child breathes on the way to the doctor’s office or Emergency Department often helps resolve the symptoms prior to arrival. Substitute juices for milk products. Frequent sips of clear liquids can loosen mucus and prevent dehydration, which often occurs with croup.
Crying can trigger spasmodic coughing. Attempt to comfort your child to prevent agitation.
Humidified oxygen or cool mist is usually given to children coming to the hospital with croup. This treatment helps to moisten secretions and inflamed tissues to open the airway and soothe irritation. Children who are not responding to mist will receive nebulizer treatments to breathe (breathing into a machine with a face mask that generates a medication-enhanced mist). This therapy is believed to decrease the swelling in the respiratory airway. Steroid therapy has been shown to be of benefit in children with moderate to severe croup. It may be given orally, by injection, or by IV. Inhaled steroids appear to have limited value. Antibiotics have not been shown to be beneficial in the treatment of croup.
Acetaminophen (Children's Tylenol) may be given for fever. Some children will benefit from sitting up straight for ease of breathing. An infant car seat can be used for small babies. Avoid exposure to respiratory irritants such as smoke.
Most cases of croup are mild. Rarely, the airway swells enough to interfere with breathing. Ear infection and pneumonia are other rare but potentially serious complications.
To prevent croup, take the same steps you use to prevent colds and flu. Frequent hand washing is most important. Keep the child away from anyone who's sick, and encourage your child to cough or sneeze into his or her elbow. To stave off more serious infections, keep your child's immunizations current. The diphtheria, Haemophilus influenzae type b (Hib) and measles vaccines offer protection from some of the rarest but most dangerous forms of croup.