Eosinophilic asthma is different from what may come to mind when you think of asthma. It may need different treatment. And it often affects those you might not think of: adults.
The differences between eosinophilic asthma and other types of asthma.
When you have asthma, the airways in your lungs become inflamed and narrow. They also produce too much mucus. This causes spasms in the tubes that move air in and out of your lungs (bronchial tubes). The spasms make breathing difficult. In addition, you may wheeze and cough. It is a lifelong condition.
There are different types of asthma. Each has different causes. These can include over-exercising or triggers that are in the air such as smoke or pollen.
One type of serious asthma is called eosinophilic asthma. It is more difficult to control with common medications. Science says it may be related to a high level of a type of white blood cell, called eosinophils, in the blood. Eosinophils are part of your immune system. They help destroy things that shouldn't be in your body, such as harmful bacteria. They also help control inflammation.
Researchers have found that the more eosinphils you have in your blood, the more likely you are to have a serious asthma attack. But they are not sure what causes eosinophil numbers to rise. They have learned that eosinophilic asthma is different from other types of asthma for several reasons:
Whom it affects
Many times asthma begins in childhood, but eosinophilic asthma usually first presents in middle adulthood.
Although this type of asthma does occur in children and adults, it commonly begins between the ages of 35 and 50. It is not known how many people have it. But researchers believe that less than 10% of people with asthma have a type as serious as eosinophilic asthma. They have also found that this type of asthma affects women and men equally.
Causes and symptoms
Many times an allergy to pollen or pet dander may trigger asthma symptoms. But people with eosinophilic asthma usually do not have these allergies. What differentiates this from other types of asthma is a high number of eosinophils in the blood, lung tissue, and phlegm (sputum).
Symptoms such as wheezing, coughing, and shortness of breath are present in all types of asthma. But in this one they affect the entire respiratory system. This means you may have many sinus infections. You may also have nasal polyps, benign (non-cancerous) growths in the nostrils or sinuses. In addition, you may notice that the lining of your nose (mucous membrane) becomes inflamed or irritated.
Your symptoms may not look or feel like those commonly associated with asthma. They may be more like those that occur with chronic obstructive pulmonary disease (COPD). This is a lung disease that causes long-term breathing problems and decreased airflow. Doctors sometimes diagnose eosinophilic asthma as COPD by mistake.
Diagnosis
To find out if you have asthma, your doctor will do a physical exam. He or she will ask you about your symptoms and other health problems. You may also have a lung function test. This will tell you how much air you can breathe out and how fast you can breathe it in.
To diagnose eosinophilic asthma you may need other tests that detect the presence of eosinophils:
-
Blood test. A doctor or nurse draws your blood to measure the number of eosinophils it contains.
-
Sputum sample. You will get a sample of coughed mucus or phlegm. Your doctor will examine it under a microscope.
-
Bronchial biopsy. This test is less common. Your doctor will insert an instrument called a bronchoscope through your nose or mouth. He or she will use it to obtain several small samples of tissue from your lungs (biopsy). The samples will be tested for the presence of eosinophils. You will need anesthesia and may have to stay in the hospital.
Treatment
The goals for the treatment of this type of asthma are twofold: to control breathing and to reduce the number of eosinophils. You may feel relief of your symptoms with common asthma treatments. These include medicines that reduce inflammation (corticosteroids) and quick-relief inhalers (bronchodilators).
But these medications do not always work for people with eosinophilic asthma. Your doctor may also give you a medicine known as a biologic. It limits the body's ability to produce eosinophils. You will take the medicine along with other asthma medicines. Antibiotics may also be part of your treatment if you have recurrent sinus infections.
Getting diagnosed and treated as quickly as possible is important to control the lasting damage this condition can cause to your lungs, such as scarring of lung tissue and thickening of the airways. Talk to your doctor once a year about your treatment and make sure it is still the best option for you.
