儿童迁延性细菌性支气管炎的定义及发病机制

Definition and pathogenesis of protracted bacterial bronchitis in children

迁延性细菌性支气管炎（PBB）是引起儿童慢性湿性咳嗽的常见原因之一。最初基于微生物学的PBB定义如下：湿性咳嗽持续〉4周，缺乏提示其他原因引起慢性咳嗽的特异性症状和特征；支气管肺泡灌洗液细菌培养阳性，且定量培养≥10^7cfu／L；抗生素（通常为阿莫西林-克拉维酸钾）治疗2周以上咳嗽可缓解。近年来又提出了临床诊断的PBB定义、难治性PBB及反复发作性PBB，以增加其临床适用度。目前研究认为，PBB的发病机制包括细菌生物被膜形成、呼吸道黏液-纤毛清除功能障碍及中性粒细胞性呼吸道炎性反应、免疫功能紊乱、抗生素使用不当等。

Protracted bacterial bronchitis （PBB） is a common cause of children with chronic wet cough. Original microbiologic- based case of PBB was defined as wet cough （ 〉4 weeks） without signs of another cause,bacterial pathogens growing and quantitative culture ≥ 10^7 cfu/L in bronchoalveolar lavage fluid and cough resolved following a 2 -week course of an appropriate oral antibiotics （usually amoxicillin -clavulanate）. In recent years, clinical -based case definition of PBB,refractory PBB and recurrent PBB have been proposed to increase its clinical applicability. At present, the pathogenesis of PBB including biofilm formation, impaired airway muco - ciliary clearance, neutrophil in- flammation, immune dysfunction and inappropriate use of antibiotics.