Eosinophilic bronchitis (EB): EB was first reported by Gibso in 1989, and a recent prospective study revealed that EB accounts for 13.5% of patients with chronic cough in adults.EB is thought to be an important cause of chronic cough in adults, but its incidence in children is unclear. The clinical features and diagnostic clues of EB are: (1) chronic irritant cough; (2) normal chest X-ray; (3) normal pulmonary ventilation without airway hyperresponsiveness; (4) sputum eosinophil relative percentage >3%; and (5) effective oral or inhaled glucocorticoid therapy.