Getting an asthma diagnosis can be tricky in some cases, as some patients do not show obvious signs of the disease once they see their doctor. Once you are away from the situation that brought on your asthma symptoms, your or your child’s asthma may have improved by the time you see the doctor. Asthma may not act up again for several days, weeks or months, which can make an asthma diagnosis difficult. However, if your doctor suspects you may have asthma, there are several tests that can be run to get an accurate diagnosis.
Typical Asthma Tests at the Doctor’s Office
There are several tests your doctor can do right in his office. These are simple, non-invasive tests that will include lung function tests. Here is a list of tests your doctor may perform:
1. Medical history. Your doctor will take a family medical history, and will then ask you about your symptoms. You will be asked if you have allergies, if you have noticed when your symptoms appear and what symptoms you have each time. You may also be asked about your diet, where and how you spend your day (work, school, gym, etc.), and if you smoke or are exposed to secondhand smoke.
• Keeping a symptom journal will be a helpful diagnostic tool for you and your doctor. In a symptom journal, you note the date, time and place you have symptoms. Then write down any and all symptoms that are taking place at that time and place. You should also include a note of when symptoms resolved, and if any medication was used or needed to help your symptoms.
2. In-office tests. Once your doctor has taken your family and medical history, they will then perform some simple in-office tests. These may include the following tests:
• Physical exam: a physical exam for asthma typically includes your doctor listening to your heart and lungs (looking for signs of wheezing, coughing or other symptoms), checking your nose and sinuses (congestion, runny nose, pain), and might include the doctor checking your skin for signs of hives or eczema.
• Spirometry: this is a lung function test that measure how much air a person can exhale. This test will show any airway obstruction, and show if your asthma medicines are working (if you’ve already been diagnosed with asthma). These tests are best for patients who are 5 years of age and older.
• Peak Flow: This test can be done in the doctor’s office and can also be done in your own home, using a peak flow meter. Peak flow is similar to a spirometry reading at your doctor’s office, but is not quite as accurate. However, if you use your peak flow meter consistently and accurately record your pf numbers, peak flow readings can help to show you when you’re having an asthma flare or attack. Peak flow measurements are easy—you blow as hard and as long as you can into the mouthpiece of a peak flow meter. You take three different readings, and then record the highest of these three readings. That will be your peak flow for that specific time and date. You can track or peak flow with an asthma diary or with an asthma app.
Additional Tests for Asthma
Sometimes it’s necessary to run further tests in order to make an accurate asthma diagnosis. Your doctor may do these tests in his office, or may need to send you to a specialist, such as a pulmonologist, for further lung tests. Here is a list of additional asthma tests that may be needed:
1. Chest x-ray: A chest x-ray is just that—an x-ray of your chest. A chest x-ray may show signs of asthma or other conditions to help determine the underlying problem causing your symptoms.
2. Methocholine Challenge: a methocholine challenge involves a patient inhaling nebulized methocholine. Methocholine is a chemical that can bring on bronchospasm in a person who may have asthma. Bronchospasm causes tightness in the chest, wheezing and or coughing; similar symptoms to an actual asthma attack. After inhaling the methocholine, you will be instructed to do a spirometry test by blowing out all the air in your lungs as fast and hard as possible. A technician or doctor will evaluate the readings from your spirometry test to determine if you have asthma. This test may be done one or more times in order to get an accurate evaluation of your possible asthma symptoms. In this case, you will be given a bronchodilator medication in between each test. This helps to relieve any symptoms you may have experienced after methocholine inhalation.
3. Exhaled nitric oxide test: This test is done by breathing into a tube attacked to a machine. The machine tests for the presence of nitric oxide gas in the air you exhale. High levels of nitric oxide may mean have inflamed airways, which is a sign of asthma.
One note, children under 5 years of age are usually not given lung function tests, as these tests are generally not accurate in young children.
Additionally, your doctor will look for signs of other lung diseases, bronchiolitis (a virus that causes asthma-like symptoms), heart failure, tumors, and vocal cord dysfunction (a problem with the movement of your vocal cords). Further testing could involve blood tests, allergy tests (to see if you have allergic asthma), sinus x-rays, Gastroenso phageal reflux disease (GERD), examination of the mucous in your lungs (looking for infection).
Asthma Diagnosis Can Take Time
Asthma can be difficult to diagnosis, but it may take some patience and time to ensure a proper and accurate diagnosis. Once your asthma’s been diagnosed and classified, your doctor will need to determine the proper medications to help your asthma. It may take some time to find the asthma medications that work for you. Once your asthma is stable with the right meds, then you and your doctor can work on creating an action asthma plan. The action plan becomes a guide on how to treat your asthma.
An accurate asthma diagnosis will help you to feel better and have a healthy, happy life in spite of asthma.