Croup

Definition

Croup is a common childhood ailment. Typically, it arises from a viral infection of the larynx (voice box) and is associated with mild upper respiratory symptoms such as a runny nose and cough. The key symptom is a harsh barking cough. Croup is usually not serious and most children recover within a few days. In a small percentage of cases, a child develops breathing difficulties and may need medical attention.

Description

At one time, the term croup was primarily associated with diphtheria, a life-threatening respiratory infection. Owing to widespread vaccinations, diphtheria has become rare in the United States, and croup currently refers to a mild viral infection of the larynx. Croup is also known as laryngotracheitis, a medical term that describes the inflammation of the trachea (windpipe) and larynx.

Parainfluenza viruses are the typical root cause of the infection, but influenza (flu) and cold viruses may sometimes be responsible. All of these viruses are highly contagious and easily transmitted between individuals via sneezing and coughing. Children between the ages of 3 months and 6 years are usually affected, with the greatest incidence at one to two years of age. Croup can occur at any time of the year, but it is most typical during early autumn and winter. The characteristic harsh barking of a croupy cough can be very distressing, but it rarely indicates a serious problem. Most children with croup can be treated very effectively at home; however, 1-5% may require medical treatment.

Croup may sometimes be confused with more serious conditions, such as epiglottitis or bacterial tracheitis. These ailments arise from bacterial infection and must receive medical treatment.

Causes & symptoms

Owing to an upper respiratory viral infection, the larynx and trachea may become inflamed or swollen. The hallmark sign of croup is a harsh, barking cough. This cough may be preceded by one to three days of symptoms that resemble a slight cold. A croupy cough is often accompanied by a runny nose, hoarseness, and a low fever. When the child inhales, there may be a raspy or high-pitched noise, called stridor, owing to the narrowed airway and accumulated mucus. In the presence of stridor, medical attention is required.

However, the airway rarely narrows so much that breathing is impeded. Symptoms usually abate completely within a few days. Medical treatment may be sought if the child's symptoms do not respond to home treatment.

Emergency medical treatment is required immediately if the child has difficulty breathing, swallowing, or talking; develops a high fever (103°F/39.4°C or more); seems unalert or confused; or has pale or blue-tinged skin.

Diagnosis

Croup is diagnosed based on the symptoms. If symptoms are particularly severe, or do not respond to treatment, an x ray of the throat area is done to assess the possibility of epiglottitis or other blockage of the airway.

Treatment

Home treatment is the usual method of managing croup symptoms. It is important that the child is kept comfortable and calm to the best degree possible, because crying can make symptoms seem worse. Humid air can help a child with croup feel more comfortable. Recommended methods include sitting in a steamy bathroom with the hot water running or using a cool-water vaporizer or humidifier. Breathing may also be eased by going outside into cooler air. The child should drink frequently in order to stay well hydrated. To treat any fever, the child may be given an appropriate dose of acetaminophen (like Tylenol). Antihistamines and decongestants are ineffective in treating croup. Children under the age of 18 should not be given aspirin, as it may cause Reye's syndrome, a life-threatening disease of the brain.

If the child does not respond to home treatment, medical treatment at a doctor's office or an emergency room could be necessary. Based on the severity of symptoms and the response to treatment, the child may need to be admitted to a hospital.

For immediate symptom relief, epinephrine may be administered as an inhaled aerosol. Effects last for up to two hours, but there is a possibility that symptoms may return. For that reason, the child is kept under supervision for three or more hours. Another effective drug is a glucocorticoid, dexamethasone. This drug requires more time to take effect, but is longer lasting. It can be administered orally or as an injection. Another glucocorticoid, budesonide, has been used outside the United States for treating croup. It is administered as an inhaled aerosol and has been shown to be effective; however, it is not available as a treatment option in the United States.

Of the 1-5% of children requiring medical treatment, approximately 1% need respiratory support. Such support involves intubation (inserting a tube into the trachea) and oxygen administration.

Alternative treatment

Botanical/herbal medicines can be helpful in healing the cough that is commonly associated with croup. Several herbs to consider for cough treatment include aniseed (Pimpinella anisum), sundew (Drosera rotundifolia), thyme (Thymus vulgaris), and wild cherry bark (Prunus serotina). Homeopathic medicine can be very effective in treating cases of croup. Choosing the correct remedy (a common choice is aconite or monkshood, Aconitum napellus) is always the key to the success of this type of treatment.

Prognosis

Croup is a temporary condition and children typically recover completely within three to six days. Children can experience one or more episodes of croup during early childhood; however, croup is rarely a dangerous condition.

Prevention

Croup is caused by highly transmissible viruses. Similar to other common childhood ailments, prevention is not applicable.

Key Terms

Diphtheria

A serious, frequently fatal, bacterial infection that affects the respiratory tract. Vaccinations given in childhood have made diphtheria very rare in the United States.

Epiglottitis

A bacterial infection that affects the epiglottis. The epiglottis is a flap of tissue that prevents food and fluid from entering the trachea. The infection causes it to become swollen, potentially blocking the airway. Other symptoms include a high fever, nonbarking cough, muffled voice, and an inability to swallow properly (possibly indicated by drooling).

Glucocorticoid

A hormone that helps in digestion of carbohydrates and reduces inflammation.

Larynx

Commonly called the voice box, it is the area of the trachea that contains the vocal cords.

Stridor

The medical term used to describe the high-pitched or rasping noise made when air is inhaled.

Trachea

Commonly called the windpipe, it is the air pathway that connects the nose and mouth to the lungs.

Further Reading

For Your Information

Periodicals

• Folland, David S. "Treatment of Croup: Sending Home an Improved Child and Relieved Parents." Postgraduate Medicine 101 (no. 3)(March 1997): 271.
• Pappas, Diane E., Gregory F. Hayden, and J. Owen Hendley. "Epiglottitis and Croup: Keys to Therapy at Home and in the Hospital." Consultant 37 (no. 4)(April 1997): 857.

Gale Encyclopedia of Medicine. Gale Research, 1999.