Abstract: Objective　To explore the value of bronchoscopy and bronchoalveolar lavage in the diagnosis and treatment of recurrent wheezing diseases in young children. Method　The results of bronchoscopy and bronchoalveolar lavage fluid (BALF) were collected from 415 children aged 1-36 months with recurrent wheezing. Seven common respiratory viruses were detected by direct immunofluorescence assay. Mycoplasma pneumoniae, Chlamydia pneumoniae and human bocavirus were detected by fluorescence quantitative PCR. Human rhinovirus and human metapneumovirus were detected by RT-PCR. The bacterial culture and cell morphology examination were also performed. During the same period, 106 non-wheezing children who were hospitalized for bronchopneumonia or lobar pneumonia with atelectasis and underwent bronchoscopy and alveolar lavage were selected as the control group. The BALF was collected for morphological examination. Results　Among the 415 wheezing children (317 males, 98 females), endobronchial inflammation was observed under bronchoscopy in 405 cases (97.6%), followed by tracheal softening in 69 cases (16.6%). Mycoplasma pneumoniae was the most common pathogen detected in BALF (159 cases, 38.3%), followed by bacteria (74 cases, 17.8%) that mainly were Streptococcus pneumoniae and Haemophilus influenzae and 69 cases of virus (16.6%) that mainly were human bocavirus. The proportion of neutrophils and eosinophils in BALF in children with recurrent wheezing was higher than that in non-wheezing children, while the proportion of phagocytic cells was lower than that in non-wheezing group (all P<0.05). Conclusion　Bronchoscopy can provide effective help for the early diagnosis and treatment to recurrent wheezing in children.

Key words: 　recurrent wheezing;　bronchoscopy;　bronchoalveolar lavage fluid;　etiology;　cytomorphology