Bronchiolitis

DEFINITION

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Bronchiolitis is a common lung infection in young children and infants. It causes congestion in the small airways (bronchioles) of the lung. Bronchiolitis is almost always caused by a virus. Typically, the peak time for bronchiolitis is during the winter months.

Bronchiolitis starts out with symptoms similar to those of a common cold but then progresses to coughing, wheezing and sometimes difficulty breathing. Symptoms of bronchiolitis can last for several days to weeks, even a month.

Most children get better with supportive care at home. A very small percentage of children require hospitalization.

CAUSES

Bronchiolitis occurs when a virus infects the bronchioles, which are the smallest of the airways branching off the main breathing tubes (bronchi) within your lungs. The viral infection makes the bronchioles swell and become inflamed. Mucus collects in these airways, which can make it difficult for air to flow freely into and out from the lungs.

Most cases of bronchiolitis are caused by the respiratory syncytial virus (RSV). RSV is a common virus which infects just about every child by the age of 2. Seasonal outbreaks of RSV infection occur every winter. Bronchiolitis can also be caused by a variety of other viruses, including those that cause the flu or the common cold.

Bronchiolitis is a contagious condition. You contract the virus just as you would a cold or the flu — through droplets in the air when someone who is sick coughs, sneezes or talks. You can also contract bronchiolitis by touching shared objects — such as utensils, towels or toys — and then touching your eyes, nose or mouth.



SYMPTOMS

For the first few days, the signs and symptoms of bronchiolitis are similar to those of a common cold:

  • Runny nose
  • Stuffy nose
  • Cough
  • Slight fever (not always present)

After this, there may be a week or more of breathing difficulty or a whistling noise when breathing out (wheezing).

Many infants will also have an ear infection (otitis media).

When to see a doctor

If it’s difficult to get your child to eat and his or her breathing becomes more rapid or labored, contact your child’s doctor. This is especially true if your child is younger than 12 weeks old or has other risk factors for bronchiolitis — including premature birth or a heart or lung condition.

The following signs and symptoms are reasons to seek prompt medical attention:

  • Vomiting
  • Breathing very fast — more than 60 breaths a minute — and shallowly
  • Skin turning blue, especially the lips and fingernails (cyanosis)
  • Lethargy
  • Refusal to drink enough fluids, or breathing too fast to eat or drink
  • Audible wheezing sounds
  • Ribs seem to suck inward when infant inhales