The Series of Tests Regularly Used to Diagnose Asthma

Asthma is a common but chronic condition that can often go undiagnosed with sufferers failing to realise that symptoms such as breathlessness, wheezing and coughing are actually caused by asthma. Those who do show these signs of the illness should consult their GP and advise on when and how often the symptoms occur. There may be an obvious trigger that induces the symptoms and you should advise your doctor if you’re aware of such a trigger. An asthma diagnosis is confirmed by tests that examine lung function while further tests will look for indications of any allergic reactions to, for example, pollen or food.

One such breathing test is done with a spirometer machine to demonstrate if your lungs are working fully. The spirometry test assesses how much you breathe in and how much your breathe out, then compares those readings against the expected breath measurements for your age to ascertain if your lung function is impaired by obstructed airways. Your GP may ask you to use a reliever inhaler, then taking a second reading. If the results are higher after using the inhaler, it can confirm an asthma diagnosis.

A peak expiratory flow rate test is another measure of lung function. A small device called a peak flow meter will measure how much air you can blow in a single breath to determine your Peak Expiratory Flow Rate (PEFR). Recording your PEFR regularly can identify if your condition is deteriorating.

Further tests can be carried out to establish which triggers are responsible for setting off your asthma symptoms. Airways responsiveness tests involve inhaling a dry powder, then breathing into the spirometer to measure how much your breathing has changed. Airways can also become inflamed because of a high concentration of nitric oxide in your breath and a test to measure this can be carried out. Another simple test to reveal potential inflammation is through a sample of phlegm.

Some asthma is triggered by allergies, particularly to pollen, dust mites and certain foods. Skin and blood tests may be used to confirm if such an allergy is the cause.