Wheezing and Asthma in Infants

More than 6 million children under the age of 18 have asthma. The majority of kids with asthma develop symptoms by age 6, and many even develop symptoms by age 3. If your infant has a cold and is lung function tests, which often involve taking a deep breath and blowing out as fast as the person can. This type of testing may show asthmatic changes in the lungs.

The mechanics of a baby's lungs also complicate the diagnosis of asthma. Infants' airways are small. When a baby gets a respiratory tract infection, these already small passages get swollen and filled with mucus much more easily than an older child's or an adult's. This can lead to coughing, wheezing, and other symptoms of asthma (even if it is not asthma, but just a viral infection).

One common condition that mimics asthma in infants is respiratory syncytial virus (RSV). The infection affects the tiny airways called bronchioles. The airways swell, making it difficult for a child to breathe. Infants are often affected because their airways are so small that they become blocked more easily than those of older kids or adults.

Symptoms of bronchiolitis include rapid breathing, a cough, wheezing, and fever. Infants who develop bronchiolitis may be more likely to develop asthma later in life. But it's unclear if that's because RSV infection causes asthma or because the child was born with a tendency to wheeze and was therefore more prone to both bronchiolitis and asthma. Studies are being done to clarify the relationship between bronchiolitis and the later development of asthma.

There are also less common reasons for wheezing in infants. A foreign object or piece of food inhaled into the lungs may cause wheezing. Cystic fibrosis can cause a child to wheeze, too, but it usually involves additional symptoms such as delayed growth.

Delaying Asthma Diagnosis

It's important to remember that just one instance of wheezing isn't enough to diagnose asthma. It must happen more than once. But even when wheezing happens on a recurring basis, a doctor may still not be certain the cause is asthma, especially in young children. More time, and sometimes more tests, may be needed to confirm the diagnosis and decide on the best long-term management plan for the child.

Doctors want to avoid an incorrect diagnosis, which might unnecessarily disrupt the lives of the entire family or label a child with a chronic condition he or she may not have. Fewer than one third of all infants who wheeze on a recurring basis during their first 3 years continue to wheeze into later childhood. In other words, most kids who wheeze as infants outgrow it and don't have asthma when they get older.

However, doctors know that uncontrolled and persistent asthma can damage the lungs over time. The early use of anti-inflammatory medications may help prevent this from happening.

For these reasons, doctors might choose to treat the symptoms as if the child has asthma, even if the diagnosis is uncertain. They may prescribe asthma medications, but probably won't officially diagnose a child with asthma unless he or she continues to have symptoms.

Diagnosing Asthma in Older Babies

You should talk to your doctor about possible asthma if your child has:

• wheezing that has happened more than once (with or without illness)
• constant or bouts of coughing that get worse at night or after active playing
• any other breathing problem that concerns you

The doctor also may ask you whether your child has breathing problems in different circumstances, such as during a cold, or when exposed to:

• cold air
• inhaler with a nebulizer.

  You should also review the treatment plan with anyone who takes care of your child. Ensure that caregivers understand the plan, and, if your child needs asthma medicine, teach them and family members how to use the inhaler or nebulizer.

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  Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
  
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