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Asthma Basics

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About Asthma

Asthma is a common lung condition in kids and teens. It causes breathing problems, with symptoms like coughing, wheezing, and shortness of breath. Anyone can have asthma, even babies, and the tendency to develop it often runs in families.

Asthma affects the bronchial tubes, or airways. When someone breathes normally, air goes in through the nose or mouth and then into the trachea (windpipe), through the bronchial tubes, into the lungs, and finally back out again.

But people with asthma have inflamed airways that produce lots of thick mucus. The airways also are overly sensitive (or hyperreactive) to certain things, like exercise, dust, or cigarette smoke. This hyperreactivity makes the smooth muscle that surrounds the airways tighten up. The combination of airway inflammation and muscle tightening narrows the airways and makes it hard for air to move through.

What Happens During an Asthma Flare-Up?

More than 25 million people have asthma in the United States. In fact, it's the No. 1 reason kids chronically miss school. And flare-ups are the most common cause of pediatric emergency room visits due to a chronic illness.

Some kids have only mild, occasional symptoms or only show symptoms after exercising. Others have severe asthma that, if not treated, can greatly limit how active they are and cause changes in lung function.

But thanks to new medicines and treatment strategies, kids with asthma don't need to sit on the sidelines and their parents don't need to worry constantly. With knowledge and the right asthma management plan, families can learn to better control symptoms and asthma flare-ups, letting kids do just about anything they want.

About Asthma Flare-Ups

Many kids with asthma can breathe normally for weeks or months between asthma flare-ups (also called asthma attacks, flares, episodes, or exacerbations) that cause the airways to narrow and become blocked, making it hard for air to move through them.

Flare-ups often seem to happen without warning, but they usually develop over time during a complicated process of increasing airway blockage.

All children with asthma have airways that are inflamed, which means that they swell and produce lots of thick mucus. And their airways are overly sensitive, or hyperreactive, to certain asthma triggers.

When exposed to these triggers, the muscles surrounding the airways tend to tighten, which makes the already clogged airways even narrower. Things that trigger flare-ups differ from person to person. Some common triggers are exercise, allergies, viral infections, and smoke.

So an asthma flare-up is caused by three important changes in the airways:

  1. swelling of the lining of the airways
  2. excess mucus that causes congestion and mucus "plugs" that get caught in the narrowed airways
  3. bronchoconstriction, the tightening of the muscles around the airways

Together, the swelling, excess mucus, and bronchoconstriction narrow the airways and make it difficult to move air through (like breathing through a straw). During an asthma flare-up, kids may have coughing, wheezing (a breezy whistling sound in the chest when breathing), chest tightness, an increased heart rate, sweating, and shortness of breath.

How Is Asthma Diagnosed?

Diagnosing asthma can be tricky and time-consuming because kids with asthma can have very different symptoms. For example, some kids cough constantly at night but seem fine during the day, while others seem to get a lot of chest colds that linger. It's common for kids to have symptoms like these for months before being seen by a doctor.

When considering a diagnosis of asthma, a doctor rules out other possible causes of the symptoms. He or she asks questions about the family's asthma and allergy history, performs a physical exam, and might order a chest X-rays or lung function tests.

During this process, parents will give the doctor such detailed information as:

This information helps the doctor understand the pattern of symptoms, which can help determine what type of asthma the child has and how best to treat it.

To confirm the diagnosis of asthma, a breathing test may be done with a spirometer, a machine that analyzes airflow through the airways. A spirometer also can be used to see if the child's breathing problems can be helped with medicine, which is a primary sign of asthma.

The doctor may take a spirometer reading, give the child an inhaled medication that opens the airways, and then take another reading to see if breathing improves. If the medicine eases airway narrowing significantly, then there's a strong possibility that the child has asthma.

If your child is diagnosed with asthma, it's important to learn how to manage asthma so it won't control your family. Educate yourself about asthma and learn to identify and eliminate triggers.

Help your child keep an asthma diary, develop and follow an asthma action plan, and take medicines as prescribed. Also, a peak flow meter — a handheld tool that measures breathing ability — can be used at home. When peak flow readings drop, it's a sign of increasing airway inflammation.

Exercise-Induced Asthma

Kids who have exercise-induced asthma (EIA) develop asthma symptoms after being very active (running, swimming, biking, etc.). Some develop symptoms only after physical activity, while others have additional asthma triggers.

With the proper medicines, most kids with EIA can play sports like other kids. In fact, asthma affects more than 20% of elite athletes, and 1 in every 6 Olympic athletes, according to the American Academy of Allergy, Asthma, and Immunology.

Usually, a doctor can diagnose EIA after taking a medical history. But sometimes more tests, including an exercise challenge in a lung function laboratory, are done confirm the diagnosis. The doctor might want to focus on a child's tolerance for a particular exercise, as not every type or intensity of exercise affects kids with EIA the same way.

If exercise is the only asthma trigger, the doctor may prescribe a medicine to be taken before exercising to prevent airways from tightening up. Even after kids take a preventive medicine, though, asthma flare-ups can still happen. So parents or older kids should carry the proper quick-relief medicine (also called rescue or fast-acting medicine) to all games and activities. Quick-relief medicines work immediately to relieve asthma symptoms.

Tell the school nurse, coaches, club leaders (Boy Scouts, Girl Scouts, etc.), teachers, and any other caregivers about your child's asthma care plan so that he or she can take medication as needed when away from home.

Allergy-Triggered Asthma

About 75% to 85% of people with asthma have some type of allergy. Even if the main triggers are colds or exercise, allergies can sometimes play a minor role in making asthma worse.

How do allergies cause flare-ups in kids with asthma? Kids inherit the tendency to have allergies from their parents. With any kind of allergy, the immune system overreacts to normally harmless allergens. Those substances (such as pollen) can cause allergic reactions in some people. As part of this overreaction, the body produces an antibody — called immunoglobulin E (IgE) — that recognizes and attaches to the allergen when the body is exposed to it.

When this happens, it starts a process that ends in the release of certain substances in the body. One of them is histamine, which causes allergic symptoms that can affect the eyes, nose, throat, skin, gastrointestinal tract, or lungs. When the airways in the lungs are affected, symptoms of asthma can happen.

The released histamine is what causes the familiar sneezing, runny nose, and itchy, watery eyes associated with some allergies — ways the body attempts to rid itself of the invading allergen. In kids with asthma, histamine also can trigger asthma symptoms and flare-ups.

An allergist can usually pinpoint allergies. Once they're identified, the best treatment is to avoid exposure to them whenever possible, such by taking environmental control measures inside the home.

When triggers can't be avoided, antihistamine medicines (to block the release of histamine in the body) or nasal steroids (to block allergic inflammation in the nose) might be prescribed. In some cases, an allergist can prescribe immunotherapy, a series of allergy shots that gradually make the body unresponsive to specific allergens.

Asthma Categories

The severity of a child's asthma symptoms will fall into one of four main categories of asthma, each with different characteristics and requiring different treatment approaches:

  1. Mild intermittent asthma
    A child who has brief episodes of wheezing, coughing, or shortness of breath no more than twice a week is said to have mild intermittent asthma. Symptoms between flare-ups are rare, with one or two instances per month of mild symptoms at night.
  2. Mild persistent asthma
    Kids with episodes of wheezing, coughing, or shortness of breath more than twice a week but less than once a day are said to have mild persistent asthma. Symptoms usually happen at least twice a month at night and flare-ups may affect normal physical activity.
  3. Moderate persistent asthma
    Kids with moderate persistent asthma have daily symptoms and need daily medicine. Nighttime symptoms happen more than once a week. Flare-ups occur more than twice a week, last for several days, and usually affect normal physical activity.
  4. Severe persistent asthma
    Kids with severe persistent asthma have symptoms continuously. They tend to have frequent flare-ups that may require emergency treatment and even hospitalization. Many kids with severe persistent asthma have symptoms at night and can handle only limited physical activity.

Asthma severity can both worsen and improve over time, placing a child in a new asthma category that needs different treatment.

All kids with asthma should follow a custom asthma action plan to control symptoms. And even mild asthma should never be ignored because airway inflammation is present even in between flare-ups.

Reviewed by: Elana Pearl Ben-Joseph, MD
Date reviewed: January 2014
Originally reviewed by: Nicole A. Green, MD

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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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