患儿男,7岁。因干咳2年于2004年2月来诊。患儿于2年前感冒后咳嗽、咳白痰,经静滴抗生素,口服止咳、化痰药治疗,咳痰症状消失,但遗有非痉挛性干咳,时轻时重。6个月前在当地医院诊断为咳嗽变异性哮喘,应用肾上腺皮质激素、支气管扩张剂、多种抗生素和止咳剂等治疗2个月无效。体检 Children male, 7 years old. 2 years due to dry cough in February 2004 to the clinic. Children 2 years ago after a cold cough, cough white sputum, intravenous antibiotics, oral cough, phlegm treatment, sputum symptoms disappear, but left with non-spasmodic dry cough, when light weight. Cough variant asthma was diagnosed at a local hospital 6 months ago and was ineffective for 2 months after treatment with corticosteroids, bronchodilators, multiple antibiotics and antitussives. Physical examination