炎症性肠病合并艰难梭菌感染患者的肠道菌群研究

Analysis of gut microbiota in inflammatory bowel disease patients with Clostridium difficile infection

目的探究合并艰难梭菌感染(CDI)的炎症性肠病(IBD)患者的肠道菌群特征。方法采用横断面研究方法,连续纳入2017年11月至2018年4月在北京协和医院就诊的IBD患者54例。根据是否合并CDI,将患者分为CDI组(n=20)和非CDI组(n=34)。同时设健康对照40例。采用16S rRNA测序技术进行肠道菌群的测定,比较3组样本肠道微生物多样性和物种组成的差异。结果与健康对照组相比,非CDI组和CDI组α多样性(Chao1指数、Shannon指数、Simpson指数、Pielou指数)更低(均P<0.05)。两组与健康对照组在β多样性(肠道菌群结构)的差异均存在统计学意义(均P<0.05)。CDI组和非CDI组间α多样性及β多样性差异均无统计学意义(均P>0.05)。与健康对照组相比,非CDI组和CDI组中粪杆菌属相对丰度更低,而变形菌门和肠杆菌科相对丰度更高,差异均具有统计学意义(均P<0.05)。与非CDI组相比,CDI组副拟杆菌属和罗斯氏菌属相对丰度更低,而拟梭菌属相对丰度更高,差异均具有统计学意义(均P<0.05)。Lefse分析显示活泼瘤胃球菌、梭菌属的无害梭菌和类腐败梭菌、香肠乳杆菌以及消化链球菌科是CDI组中对差异贡献显著的标志物种。结论与健康人群及未合并CDI的IBD患者相比,IBD合并CDI患者肠道菌群物种组成存在特异性改变。

Objective To explore the character of gut microbiota in inflammatory bowel disease(IBD)patients with Clostridium difficile infection(CDI).Methods A cross-sectional study was conducted.Fifty-four IBD patients were included consecutively in Peking Union Medical College Hospital from November 2017 to April 2018.The patients were divided into CDI group(n=20)and non-CDI group(n=34)according to whether the patient had CDI.Forty healthy people were recruited as the healthy control group.16S rRNA sequencing was carried out in all the samples of 3 groups to analyze the diversity and composition of gut microbiota.Results Compared with the healthy control group,αdiversity(Chao1 index,Shannon index,Simpson index,Pielou index)was significantly lower andβdiversity(microbiota structure)was significantly different in CDI and non-CDI groups(all P<0.05).There was no significant difference inαandβdiversities between CDI and non-CDI groups(all P>0.05).Compared with healthy control group,relative abundance of Faecalibacterium was significantly lower in CDI and non-CDI groups,while relative abundances of Proteobacteria and Enterobacteriaceae were significantly higher(all P<0.05).Compared with non-CDI group,relative abundances of Parabacteroides and Rothia were significantly lower,while relative abundance of Clostridioides was significantly higher in CDI group(all P<0.05).Lefse analysis results showed that Ruminococcus gnavus,Clostridium innocuum,Clostridium paraputrificum,Lactobacillus farciminis,and Peptostreptococcaceae contributed greatly to the difference in CDI group.Conclusion Compared with healthy control group and non-CDI group,IBD patients with CDI have specific alterations in composition of gut microbiota.