Abstract: Objective  To explore the application value of fiberoptic bronchoscopy(BFS) and bronchoalveolar lavage(BAL) in diagnosis and treatment of chronic pneumonia in children. 
Methods  A total of 136 children with chronic pneumonia were enrolled in this study. Among them, 68 children who received conventional treatment were selected as the control group, and the remaining 68 cases who received combination of conventional treatment and BFS as well as BAL served as the observation group. The results of BFS and pathogen detection in bronchoalveolar lavage fluid were recorded in the observation group. The clinical efficacy, disappearance time of symptoms and signs, arterial blood gas indexes and serum inflammatory factors were compared between the two groups. The possible complications caused by BAL in BFS were monitored. 
Results  All 68 children in the observation group who received BFS showed different degrees of endobronchial inflammation, including 11 cases of airway dysplasia. The positive rate of bacterial culture in BALF was significantly higher than that in sputum culture(P＜0.05). The total effective rate of the observation group was higher than that of the control group(P＜0.05). The disappearance time of fever, cough, lung moist rales and wheezing sounds in the observation group were significantly shorter than those in the control group(P＜0.05). After treatment, the arterial partial pressure of oxygen(PaO2) and power of hydrogen(pH) in the observation group were significantly higher than those before treatment and in the control group. While the values of arterial partial pressure of carbon dioxide(PaCO2) were significantly lower than those before treatment and the control group(P＜0.05). There was no significant difference in PaO2, PaCO2 and pH in the control group before and after treatment(P＞0.05). After treatment, the serum levels of interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) in the two groups were significantly lower than those before treatment, and the levels of IL-6 and TNF-α in the observation group were lower than those in the control group(P＜0.05). In the observation group, there were 4 cases of decrease of percutaneous oxygen saturation and 6 cases of bronchial mucosal hemorrhage during the treatment of BFS with BAL, but all of them were mild and relieved after symptomatic treatment. 
Conclusion  The application of BFS in BAL treatment of children with chronic pneumonia has high clinical application value in etiological diagnosis, pathogen detection and treatment. In addition, it is well tolerated in children. 

Key words: pneumonia, bronchoscopy, bronchoalveolar lavage