Bronchiolitis is an infection of the small breathing tubes
(bronchioles) of the lungs. It occurs most often in infants.
(The term bronchiolitis is sometimes confused with bronchitis,
which is an infection of the larger, more central airways.)
Bronchiolitis is almost always caused by a virus, most
commonly the respiratory syncytial virus (RSV). Other viruses
that can cause this condition are parainfluenza, influenza,
measles, and adenovirus. The infection causes inflammation and
swelling of the bronchioles, which in turn, blocks the airflow
through the lungs. Most adults and many children who are
infected by RSV get only a cold. In infants, however, the
infection is more likely to lead to bronchiolitis. This happens
because their airways are smaller and are more easily blocked
when infection and inflammation occur.
Almost half the infants who develop bronchiolitis go on to
develop asthma later in life. We do not know why these
youngsters are more susceptible, but it is likely that the RSV
infection is the first trigger for the airway reaction.
RSV infection is the most likely cause of bronchiolitis from
October through March. It is spread by contact with secretions
from an infected person. It often spreads through families,
child-care centers, and hospital wards. Careful hand washing can
help prevent this.
If your infant has bronchiolitis, it will start with signs of
an upper respiratory infection (a cold): runny nose, mild cough,
and sometimes fever. After a day or two the cough becomes more
pronounced, the child begins to breathe more rapidly, and with
more difficulty:
- He may dilate his nostrils and squeeze the muscles under
his rib cage in efforts to get more air in and out of his
lungs.
- He will use the muscles between the ribs and above the
collarbone to help him breathe.
- When he breathes he may grunt and tighten his abdominal
muscles.
- He will make a high-pitched whistling sound, called a
wheeze, each time he exhales.
- He may not take fluids well because he is working so hard
to breathe that he has difficulty sucking and swallowing.
- As his breathing difficulty increases, you may notice a
bluish tint around the lips and fingertips. This indicates
that his airways are so blocked that an inadequate amount of
oxygen is getting into the blood.
If your baby shows any of these signs of breathing difficulty,
or if his fever lasts more than three days (or is present at all
in an infant under three months), call your pediatrician
immediately.
Call the pediatrician if your child develops any of the
following signs or symptoms of dehydration, which also can be
present with bronchiolitis.
- Dry mouth
- Taking less than his normal amount of fluids
- Shedding no tears when he cries
- Urinating less often than normal
Lastly, if your child has any of the following conditions,
notify your pediatrician as soon as you suspect that he has
bronchiolitis.
- Cystic fibrosis
- Congenital heart disease
- Bronchopulmonary dysplasia (seen in some infants who have
been on a respirator as newborns)
- Low immunity
- Organ transplant
- A cancer for which he is receiving chemotherapy
There are no medications you can use to treat RSV infections at
home. All you can do during the early phase of the illness is
ease your child's cold symptoms. You can relieve some of the
nasal stuffiness with a humidifier, nasal aspirator, and perhaps
some mild salt-solution nasal drops prescribed by your
pediatrician. Make sure your baby drinks lots of fluid during
this time so he does not become dehydrated. He may prefer clear
liquids rather than milk or formula. Because of the breathing
difficulty, he also may feed more slowly and may not tolerate
solid foods very well.
If your baby is having mild to moderate breathing difficulty,
your pediatrician may try using a bronchodilating drug (one that
opens up the breathing tubes) before considering
hospitalization.
Unfortunately, some children with bronchiolitis need to be
hospitalized, either for breathing distress or dehydration. The
breathing difficulty is treated with oxygen and bronchodilating
drugs, which are inhaled periodically. Occasionally, another
medicine, called theophylline, is used. The dehydration will be
treated with a special liquid diet or by fluids given
intravenously.
The best way to protect your baby from bronchiolitis is to
keep him away from the viruses that cause it. When possible,
especially while he's an infant, avoid close contact with
children or adults who are in the early (contagious) stages of
respiratory infections. If he is in a child-care center where
other children might have the virus, make sure that those who
care for him wash their hands thoroughly and frequently.
