WHAT IS EOSINOPHILIC ASTHMA (EA)?
Eosinophilic asthma is a common type of asthma characterized by high levels of eosinophils that can cause airway inflammation.1-3
Up to 10% of people
with asthma have
Up to 70% of severe
have eosinophilic asthma* 5
*Majority of patients with severe asthma (Grade 3 = most likely eosinophilic) had blood eosinophil count (BEC) ≥300 cells/μL OR were on anti-IL-5/IL-5R therapy. Severe disease was also characterised as BEC ≥ 150-300 cells/μL and being on maintenance oral corticosteroid (OCS), or the presence of ≥ 2 nasal polyps (NP), elevated fractional nitric oxide (FeNO) and late onset.
THE ROLE OF EOSINOPHILIC IMMUNE DYSFUNCTION IN EOSINOPHILIC ASTHMA
Eosinophils are key effector cells in eosinophilic asthma, where immune system
dysfunction leads to eosinophilic inflammation in the airway tissue.6-8
Increasing eosinophil levels in the airway are associated with increasing
severity of asthma.9
Eosinophilic asthma patients are at risk of more frequent exacerbations, poorer asthma
control, and lower lung function.10-12
Eosinophilic inflammation in the airway tissue7,13-16
In eosinophilic asthma, immune cells catalyzed by allergic or nonallergic triggers can lead
to the production of various cytokines. The cytokines produced by these cells
can contribute to the recruitment, activation, and survival of eosinophils.11,16-18
Cytokines are signaling proteins that are usually less than 80kDa in size. Through extracellular signalling, these proteins regulate a wide range of functions, including innate and acquired immunity, hematopoiesis, inflammation and repair, and proliferation.19
EOSINOPHILS ARE KEY EFFECTOR CELLS AND COULD BE THE DRIVER OF A PATIENTS SEVERE ASTHMA.6-8
HOW DO YOU IDENTIFY EOSINOPHILIC ASTHMA?
Patients with eosinophilic asthma may experience the following clinical characteristics11,20: