目的 基于Toll受体2（TLR2）/髓样分化蛋白88（MyD88）/细胞核因子-κB（NF-κB）信号通路分析纤维支气管镜肺泡灌洗（BAL）联合阿奇霉素、甲泼尼龙治疗肺炎支原体（MP）感染所致重症肺炎支原体肺炎（SMPP）患儿的效果。 方法 选择2022年1月至2024年1月武汉市第一医院儿科收治的MP感染所致SMPP患儿84例作为观察组（n = 84），均接受BAL联合常规对症治疗、阿奇霉素、甲泼尼龙治疗；另择同期MP感染所致SMPP患儿作为对照组（n = 84），接受常规对症治疗、阿奇霉素、甲泼尼龙治疗。两组均持续治疗7 d。比较两组治疗7 d后疗效，康复情况，治疗前、治疗7 d后肺功能、血气分析、TLR2/MyD88/NF-κB信号通路，治疗期间不良反应。 结果 治疗7 d后，观察组总有效率组间更高［97.62%（82/84） vs. 84.52%（71/84），P < 0.05］。观察组咳嗽、肺部啰音、退热、住院时间比对照组短（P < 0.05）。治疗7 d后，两组动脉二氧化碳分压（PaCO₂）水平，外周血中的单个核细胞（PBMC）TLR2 mRNA、MyD88 mRNA、NF-κB mRNA水平与治疗前相比下降，且观察组更低（P < 0.05）。治疗7 d后，两组达峰时间比（TPTEF/TE）、最大呼气中期流量（MMEF）、达峰容积比（VPTEF/VE）、氧合指数（OI）、动脉血氧饱和度（SaO₂）、动脉血氧分压（PaO₂）水平与治疗前相比升高，且观察组更高（P < 0.05）。治疗期间，对照组、观察组总不良反应为5.95%（5/84）、8.33%（7/84），组间比较差异无统计学意义（P = 0.549）。 结论 BAL治疗MP感染所致SMPP可改善患儿肺功能、血气分析，下调TLR2/MyD88/NF-κB信号通路，促进病情康复，效果确切，安全性良好。

Objective To investigate the efficacy and mechanism of fiberoptic bronchoscopic alveolar lavage （BAL） in combination with azithromycin and methylprednisolone in the treatment of severe Mycoplasma pneumoniae pneumonia （SMPP） through the Toll-like receptor 2 （TLR2）/myeloid differentiation factor 88 （MyD88）/nuclear factor-κB （NF-κB） signaling pathway. Methods Eighty-four cases of children with SMPP caused by Mycoplasma pneumoniae （MP） infection， who were admitted to the Pediatrics Department of Wuhan First Hospital from January 2022 to January 2024， were selected as the observation group （n = 84）. All of them received BAL combined with conventional symptomatic treatment， azithromycin， and methylprednisolone treatment. Another 84 cases of children with SMPP caused by MP infection during the same period were selected as the control group. The observation group received BAL combined with conventional symptomatic treatment， azithromycin， and methylprednisolone， whereas the control group received only conventional symptomatic treatment， azithromycin， and methylprednisolone. Both groups were treated for 7 days. Therapeutic efficacy， recovery parameters， lung function， blood gas analysis， and TLR2/MyD88/NF-κB signaling pathway markers were compared between the two groups before and after treatment. Adverse reactions were also monitored during the treatment period. Results After a 7-day treatment period， the total effective rate in the observation group was significantly higher than that in the control group ［97.62% （82/84） vs. 84.52% （71/84）， P < 0.05］. The durations of cough， pulmonary rales， fever resolution， and hospitalization in the observation group were significantly shorter than those in the control group （all P < 0.05）. After treatment， the levels of arterial partial pressure of carbon dioxide （PaCO?）， along with the expression of TLR2 mRNA， MyD88 mRNA， and NF-κB mRNA in peripheral blood mononuclear cells （PBMC）， decreased in both groups compared with the baseline values. Notably， the observation group exhibited significantly lower levels （all P < 0.05）. In contrast， the time to peak tidal expiratory flow as a proportion of expiratory time （TPTEF/TE）， maximum mid-expiratory flow （MMEF）， volume to peak expiratory flow as a proportion of exhaled volume （VPTEF/VE）， oxygenation index （OI）， arterial oxygen saturation （SaO?）， and arterial partial pressure of oxygen （PaO?） increased in both groups after treatment. The observation group showed significantly higher values （all P < 0.05）. The overall incidence of adverse reactions was 5.95% （5/84） in the control group and 8.33% （7/84） in the observation group， and there was no statistically significant difference between the two groups （P = 0.549）. Conclusion BAL， when combined with azithromycin and methylprednisolone， effectively enhances lung function and blood gas parameters， downregulates the TLR2/MyD88/NF-κB signaling pathway， and facilitates clinical recovery in children with MP-induced SMPP， exhibiting favorable efficacy and safety profiles.