What Is Eosinophilic Asthma?

Eosinophilic asthma is airway inflammation associated with large numbers of specialized white blood cells in the airway. These cells, known as eosinophils, are part of the immune system and are designed to react when the body is exposed to foreign particles and organisms. In asthma, they overreact and go on the offensive, attacking the body’s own tissue because they get confused. Research on eosinophils and asthma suggests they play an important role in the development of this common respiratory condition and are also closely involved in the exacerbation of asthma.

In patients with eosinophilic asthma, white blood cells flock to the airway, initially summoned by a chemical signal. As they appear, they produce their own signals to attract other white blood cells. This causes airway inflammation and swelling which can onset very rapidly and be dangerous for the patient. Sputum samples can reveal high levels of eosinophils, and the patient’s blood will also have an elevated white blood cell count, indicating that the patient’s immune system is responding to something.

The exact process through which eosinophilic asthma develops is not completely understood, although researchers argue that the signaling process used by white blood cells could be a therapeutic target. By halting the signaling in its tracks, doctors could arrest asthma before an exacerbation, or help a patient recover more quickly from a severe episode. Management of the condition involves administrating immunosuppressive drugs like steroids to halt the immune response. Patients can also use rescue inhalers that force the airways to dilate, making it possible to breathe.

One consequence of eosinophilic asthma is hypersensitivity in the immune system as a whole, not just the airways. The patient could be more prone to skin irritation, for example, because the body is on high alert. Asthma can be associated with issues like eczema and rashes created by autoimmune responses. Medications can be used to treat each individual outbreak to manage the patient’s condition, and people can also consider maintenance drugs to prevent incidents.

Research on eosinophilic asthma has probed into a number of aspects of how the condition develops and why patient responses may be sustained. This may help with the development of new drug therapies to prevent the onset of severe asthma attacks and treat patients more effectively during attacks. Like other autoimmune diseases, eosinophilic asthma can potentially be very serious for the patient, as uncontrolled inflammation can progress to the point of serious impairment.