[Clinical characteristics and pathogens of infancy lower respiratory tract infections in infants with bronchopulmonary dysplasia].

To study the clinical characteristics and pathogen features of infants with bronchopulmonary dysplasia (BPD) who were readmitted during infancy due to lower respiratory tract infections.A retrospective analysis was conducted on 128 preterm infants with BPD who were admitted for lower respiratory tract infections in Qingdao Women and Children's Hospital from January 2020 to December 2022. An equal number of non-BPD preterm infants admitted during the same period were selected as controls. General information, clinical characteristics, lung function parameters, and respiratory pathogen results were compared between the two groups.Compared with the non-BPD group, the BPD group had a lower gestational age and birth weight, were more likely to experience shortness of breath, wheezing, and cyanosis, and had a longer duration of wheezing relief (P<0.05). Compared with the non-BPD group, the BPD group had lower lung function parameters, including tidal volume per kilogram of body weight, ratio of time to peak tidal expiratory flow to total expiratory time, ratio of volume at peak tidal expiratory flow to expiratory tidal volume, tidal expiratory flow at 25%, 50%, and 75% of tidal volume, and increased respiratory rate (P<0.05). The detection rates of gram-negative bacteria, such as Klebsiella pneumoniae and Acinetobacter baumannii, were higher in the BPD group than in the non-BPD group (P<0.05).Infants with BPD who develop infancy lower respiratory tract infections require closer attention to the clinical characteristics such as shortness of breath, wheezing, and cyanosis. Lung function is characterized by obstructive changes and small airway dysfunction. Gram-negative bacteria, including Klebsiella pneumoniae and Acinetobacter baumannii, are more likely to be detected as respiratory pathogens.目的: 分析支气管肺发育不良（bronchopulmonary dysplasia, BPD）患儿婴儿期内因下呼吸道感染再入院的临床特征及病原体特点。方法: 选取2020年1月—2022年12月青岛市妇女儿童医院收治的因下呼吸道感染住院的BPD早产儿128例进行回顾性分析，并选择同期住院的同等例数的非BPD早产儿为对照，比较2组患儿的一般资料、临床特征、肺功能指标及呼吸道病原学结果。结果: 与非BPD组相比，BPD组患儿胎龄、体重小，更容易出现气促、喘息及发绀，喘息缓解时间长（P<0.05）。肺功能检查方面，与非BPD组相比，BPD组患儿每公斤体重潮气量、达峰时间比、达峰容积比、25%潮气量呼气流量、50%潮气量呼气流量、75%潮气量呼气流量均降低，而呼吸频率增快（P<0.05）。BPD组患儿肺炎克雷伯菌、鲍曼不动杆菌等革兰氏阴性杆菌检出率高于非BPD组（P<0.05）。结论: BPD患儿婴儿期下呼吸道感染后需更关注气促、喘息及发绀等临床特征，肺功能表现为阻塞性改变及小气道功能障碍，呼吸道病原更易检出肺炎克雷伯菌、鲍曼不动杆菌等革兰氏阴性杆菌。.