"Death" (video; 10:18) by Timothy Ferris, producer of the Voyager Golden Record for NASA. 2021
Eosinophilic bronchitis has also been linked to other conditions such as COPD, atopic cough, and allergic rhinitis. Pathophysiology
The number of eosinophils in the sputum samples of non-asthmatic eosinophilic bronchitis patients are similar to those of patients with asthma. In the sputum samples of those with NAEB, histamine and prostaglandin D2 is increased. This suggests that the superficial airways have significant mast cell activation and this may lead to the differing symptom presentation compared to asthma. Inflammation caused by eosinophils is associated with an increased cough reflex. In another study, however, some follow-up patients who were asymptomatic also had increased eosinophils in their sputum, indicating that the inflammation is not always associated with an increased cough reflex.The cause of the inflammation can be associated with environmental triggers or common allergens such as dust, chloramine, latex, or welding fumes. Diagnosis
Diagnosis of eosinophilic bronchitis is not common as it requires the examination of the patients sputum for a definitive diagnosis, which can be difficult in those who present with a dry cough. In order to induce the sputum, the patient has to inhale increasing concentrations of hypertonic saline solution. If this is unavailable, a bronchoalveolar lavage can be done, and the bronchial wash fluid can be examined for eosinophils. The diagnosis is usually considered later by ruling out other life-threatening conditions or more common diagnoses such as asthma and GERD, and by seeing an improvement in symptoms with inhaled corticosteroid treatment. Chest X-rays and lung function tests are usually normal. CT scans may show some diffuse airway wall thickening.