Department of Paediatrics, Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, No.725 South Wanping Road, Xuhui District, Shanghai, 200032, China.
Sci Rep. 2022 Apr 5;12(1):5683. doi: 10.1038/s41598-022-09700-0.
Mycoplasma pneumoniae (MP) infection is a common cause of community-acquired pneumonia in children. Furthermore, many children with Mycoplasma pneumoniae pneumonia (MPP) have recurrent wheezing and reduced small airway function after their clinical symptoms have resolved, eventually leading to asthma. MPP can trigger immune disorders and systemic inflammatory responses. Hence, the intestine is the largest immune organ of the body. Therefore, we sought to investigate whether the alteration of intestinal flora is correlated with the development of wheezing in children with MPP. We collected 30 healthy children as group A, 50 children with nonwheezing MPP as group B, and 50 children with wheezing MPP as group C. We found that the percentage of eosinophil cells (EC) was significantly higher in group C than that in group B for routine blood tests and serum inflammatory factors. The serum cytokines, including IL-4, IL-17, TNF-α, and TGF-β, were significantly higher in group C than in group B. In addition, the level of IL-10 was significantly lower in group C than in group B. The distribution characteristics of intestinal flora strains in children with MPP were detected by sequencing of 16S rRNA gene amplicon sequencing. There were differences in the abundance of intestinal flora between children with MPP and healthy children, with lower abundance of Ruminococcus flavefaciens, Clostridium butyricum, Lactobacillus, and Bifidobacterium in the intestine of children with MPP compared to healthy children. The abundance of Ruminococcus flavefaciens and Clostridium butyricum was significantly lower in the intestine of children with wheezing MPP compared to children without wheezing MPP. In the correlation analysis between children with MPP and inflammatory factors, Ruminococcus flavefaciens was found to be negatively correlated with IL-17. Clostridium butyricum was negatively correlated with L-4, IL-17, TNF-α, and TGF-β; however, it positively correlated with IL-10. Thus, it was concluded that alterations in intestinal flora play a crucial role in the immune response to MPP, where a significant decline in intestinal Ruminococcus flavefaciens and Clostridium butyricum leads to an exacerbation of the inflammatory responses, which may promote the development of children with wheezing MPP.
肺炎支原体（MP）感染是儿童社区获得性肺炎的常见病因。此外，许多患有肺炎支原体肺炎（MPP）的儿童在临床症状缓解后会反复出现喘息和小气道功能下降，最终导致哮喘。MPP 可引发免疫紊乱和全身炎症反应。因此，肠道是人体最大的免疫器官。因此，我们试图研究肠道菌群的改变是否与 MPP 患儿喘息的发生有关。我们收集了 30 名健康儿童作为 A 组，50 名非喘息性 MPP 患儿作为 B 组，50 名喘息性 MPP 患儿作为 C 组。我们发现，常规血液检查和血清炎症因子中，C 组的嗜酸性粒细胞（EC）百分比明显高于 B 组。C 组血清细胞因子，包括 IL-4、IL-17、TNF-α 和 TGF-β，明显高于 B 组。此外，C 组的 IL-10 水平明显低于 B 组。通过 16S rRNA 基因扩增子测序检测 MPP 患儿肠道菌群菌株的分布特征。MPP 患儿与健康儿童的肠道菌群丰度存在差异，MPP 患儿肠道内 Ruminococcus flavefaciens、Clostridium butyricum、Lactobacillus 和 Bifidobacterium 的丰度低于健康儿童。喘息性 MPP 患儿肠道内 Ruminococcus flavefaciens 和 Clostridium butyricum 的丰度明显低于非喘息性 MPP 患儿。在 MPP 患儿与炎症因子的相关性分析中，发现 Ruminococcus flavefaciens 与 IL-17 呈负相关。Clostridium butyricum 与 L-4、IL-17、TNF-α 和 TGF-β 呈负相关，与 IL-10 呈正相关。因此，结论是肠道菌群的改变在 MPP 的免疫反应中起关键作用，肠道内 Ruminococcus flavefaciens 和 Clostridium butyricum 的显著下降导致炎症反应加剧，可能促进喘息性 MPP 患儿的发展。
