Colorado Springs

Allergy and Asthma Clinic

"Enjoy the Beauty of Colorado

Without the Sneeze or the Wheeze!"

Screening and diagnosis

Diagnosing asthma can be difficult. Signs and symptoms can range from mild to very severe and are often similar to those of other conditions, including emphysema, early congestive heart failure or vocal cord problems.

In order to rule out these and other possible conditions, your doctor will likely use several tests to arrive at a diagnosis. In most cases you'll be asked to give a complete medical history and have a physical exam. You may also be given lung (pulmonary) function tests to determine how much air moves in and out as you breathe.

The two most common tools to measure lung function are:

• Spirometer. A spirometer is used by a medical professional to measure narrowing of your bronchial tubes. This device measures the volume of air you can exhale after you've taken a deep breath. A spirometer also shows how quickly you can get air out of your lungs.
• Peak flow meter. A peak flow meter can be used at home to help detect subtle increases in airway obstruction before you notice symptoms. If the readings are lower than usual, it's a sign your asthma may be about to flare up. Your doctor can give you instructions on how to deal with low readings.

Lung function tests often are done before and after taking a medication known as a bronchodilator to open your airways. If your lung function improves with use of a bronchodilator, it's likely you have asthma.

If there is uncertainty about a diagnosis of asthma, your doctor may also recommend a methacholine bronchial challenge. If you have asthma, inhaling a known asthma trigger called methacholine will cause mild constriction of your airways, which can be measured with a lung function test. A positive methacholine test supports a diagnosis of asthma.

How asthma is classified
The results of your physical exam and diagnostic tests can help your doctor classify how severe your asthma is, which helps guide how it should be treated. The four main classifications of asthma are:

• Mild intermittent. This is the mildest form of asthma. Generally, people with mild intermittent asthma have mild symptoms up to two days a week and up to two nights a month.
• Mild persistent. You have mild persistent asthma if you have asthma symptoms more than twice a week, but no more than once in a single day.
• Moderate persistent. If you have asthma symptoms once a day and more than one night a week, you may have moderate persistent asthma.
• Severe persistent. This is the most severe form of asthma, causing symptoms throughout the day on most days and frequently at night.

Complications

Asthma accounts for millions of missed school days and workdays each year. It's also a common reason for emergency room visits and hospitalizations. You can reduce your risk of severe attacks by making sure your asthma is well controlled and by knowing how to recognize and treat attacks before they occur.

Controlling your asthma can also help you avoid serious side effects from long-term use of some medications used to stabilize severe asthma. Using inhaled corticosteroids, which have fewer side effects than oral corticosteroids, can help you reduce the need for emergency treatment of asthma.