1. Definition: A non-asthmatic bronchitis characterized by airway eosinophil infiltration, with negative airway hyperreactivity, manifesting as a chronic cough that responds well to glucocorticoid therapy. 2, clinical manifestations: symptoms are mainly chronic cough, often the only clinical symptoms, dry cough or cough a little white mucus sputum, can be in the daytime or night cough. Some patients are more sensitive to fumes, dust, odors or cold air, which are often triggering factors for coughing. Patients do not have shortness of breath, dyspnea and other symptoms, lung ventilation function and peak expiratory flow rate variability (PEFR) is normal, and there is no evidence of airway hyperreactivity. 3, diagnosis: EB clinical manifestations lack of characteristics, local performance similar to CVA, diagnosis relies on induced sputum cytology examination (Annex 2). Detailed specifications are as follows: (1) chronic cough, mostly comforting dry cough or with large amounts of mucous sputum. (2) Normal x-ray chest film. (3) Normal pulmonary ventilation function, negative airway hyperresponsiveness test, and normal inter-day variability of peak expiratory flow rate. (4)Sputum cytology reflection of eosinophil ratio ≥2.5%. (5) Clear of other eosinophilic diseases. (6) Oral or inhaled glucocorticoids are effective. 4. Treatment: EB responds well to glucocorticosteroid treatment and the cough disappears quickly after treatment. Inhaled glucocorticosteroids are usually used for treatment.