Eosinophilic airway inflammation is a chronic respiratory condition characterized by the accumulation of specific white blood cells, called eosinophils, within the breathing passages. This persistent presence of eosinophils leads to ongoing irritation and swelling in the airways.
What Eosinophilic Airway Inflammation Is
Eosinophils are white blood cells, normally present in small numbers, that play a role in the body’s immune defense, particularly against parasites and in allergic responses, by releasing proteins and enzymes from their granules to combat threats. When the body encounters certain triggers, eosinophils are recruited to specific tissues, including the airways.
In eosinophilic airway inflammation, an excessive production and activation of eosinophils occurs within the bronchial tubes. This heightened presence releases their granular contents, causing damage and swelling to the delicate lining of the airways. The sustained inflammatory process can lead to structural changes in the airways over time, contributing to narrowing of the air passages, making breathing more difficult.
Identifying the Causes and Symptoms
Eosinophilic airway inflammation is frequently associated with severe asthma, particularly the eosinophilic subtype, driven by an overactive immune response involving eosinophils. Environmental allergens (like pollen or dust mites), certain irritants, or pollutants can trigger or worsen this inflammation. The condition can also be linked to chronic obstructive pulmonary disease (COPD) and chronic rhinosinusitis with nasal polyps.
Individuals with eosinophilic airway inflammation often present with a range of respiratory symptoms. These include persistent coughing (dry or with mucus), wheezing (a high-pitched whistling sound), shortness of breath (especially during physical activity), and a sensation of chest tightness or pressure. Symptoms can vary in intensity and frequency, sometimes leading to acute flare-ups.
How It’s Diagnosed
Diagnosing eosinophilic airway inflammation involves a thorough medical evaluation, beginning with a detailed review of symptoms and medical history. Healthcare professionals utilize several specific tests to confirm eosinophilic inflammation, including a complete blood count (CBC) with differential to reveal elevated levels of eosinophils in the bloodstream.
Sputum analysis, which examines mucus coughed up from the lungs, is another diagnostic tool. This test involves inducing sputum production and analyzing it under a microscope to directly count the percentage of eosinophils present in the airways; levels above 3% often indicate eosinophilic inflammation. Fractional exhaled nitric oxide (FeNO) testing measures nitric oxide in exhaled breath; elevated levels can suggest eosinophilic airway inflammation. Lung function tests, such as spirometry, assess how well the lungs are working by measuring airflow and lung volumes, helping to determine the extent of airway obstruction.
Treatment Options
Managing eosinophilic airway inflammation aims to reduce excess eosinophils and control inflammation to alleviate symptoms and prevent disease progression. Inhaled corticosteroids are a common first-line treatment, delivered directly to the airways to suppress inflammation and reduce eosinophil activity. For more severe cases or acute exacerbations, short courses of oral corticosteroids may be prescribed to quickly bring severe inflammation under control, though long-term use is typically limited due to potential side effects.
Biologic therapies offer a targeted approach for individuals with severe eosinophilic airway inflammation who do not respond adequately to conventional treatments. These medications, administered via injection, are monoclonal antibodies designed to block specific pathways involved in eosinophil production and activity. For example, some biologics target interleukin-5 (IL-5), a cytokine that promotes eosinophil growth and survival. Other biologics block the IL-4 and IL-13 pathways, which are also involved in allergic inflammation. These therapies aim to reduce eosinophil counts, improve lung function, and decrease the frequency of exacerbations.
Living with Eosinophilic Airway Inflammation
Living with eosinophilic airway inflammation requires consistent management and close collaboration with healthcare providers. Adherence to prescribed treatment plans, including regular use of inhaled medications and scheduled biologic injections, is important for disease control. Regular monitoring by a healthcare professional is necessary to assess treatment effectiveness and adjust therapies, often involving periodic lung function tests and blood eosinophil counts to track the condition.
Identifying and avoiding known triggers, such as specific allergens or environmental irritants, can help prevent symptom flare-ups. This might involve strategies like using air purifiers or minimizing exposure to pet dander. Maintaining a healthy lifestyle, including regular physical activity within tolerance and a balanced diet, can also support overall respiratory health. These ongoing efforts contribute to improving the quality of life for individuals managing this chronic condition.