Introduction to bronchiolitis:

Worried parents stand over the crib, listening to their baby cough and struggle to breathe. He may have bronchiolitis. Most parents have heard of pneumonia or bronchitis, but what does bronchiolitis mean?

What is bronchiolitis?

Bronchitis is inflammation of the large airways in the chest and pneumonia is inflammation of the lung. Bronchiolitis is inflammation of the smaller airways connecting the two.

Bronchiolitis is usually a viral infection. RSV is responsible for the illness in most children. Adenovirus, parainfluenza (croup), and other viruses can also cause bronchiolitis.

In adults and older children, RSV usually appears as a bad cold. However, in babies and toddlers whose bronchioles are smaller and easier to plug, these viruses often cause bronchiolitis when inhaled.

Who gets bronchiolitis?

Bronchiolitis is primarily a disease of young children before their second birthdays. The most common age for bronchiolitis is about 6 months.

Winter and early spring are bronchiolitis season. Children in day care are usually much more likely to get bronchiolitis. Kids who are exposed to cigarette smoke are at even higher risk. Babies who attend day care are less likely to get bronchiolitis than those who stay home with a parent who smokes.

Boys are more often affected, as are formula-fed infants. Those at high risk for asthma also appear to be prone to bronchiolitis.

Most kids who get bronchiolitis have been exposed to an adult or another child with a cold in the previous week.

What are the symptoms of bronchiolitis?

Bronchiolitis usually begins with cold symptoms such as a runny nose, sneezing, and perhaps a mild cough. The appetite is often decreased. The child may have a fever or might be a bit cooler than normal.

After a day or two, breathing becomes faster and the cough becomes more severe. It may be a deep or wheezy cough. The child may develop wheezing and respiratory distress.

Breathing difficulties can make it hard for babies to feed.

Is bronchiolitis contagious?

Bronchiolitis is very contagious. It spreads most commonly by contact transmission, droplet transmission, and fomites.

How long does bronchiolitis last?

Mild bronchiolitis may last only for a day or so. Often the disease lasts 5 to 12 days. The first 3 days are the most critical.

How is bronchiolitis diagnosed?

Diagnosis is often based on the history and physical exam. A chest x-ray can give additional information, as can a pulsoximeter to measure oxygen levels. A specific swab for RSV might be done to identify the cause of bronchiolitis.

How is bronchiolitis treated?

There are no specific medicines for treating bronchiolitis at home.