Objective: To investigate the differences of gastric mucosa microbiota between children with chronic gastritis and duodenal ulcer under the condition of Helicobacter pylori (Hp) infection. Methods: This prospective cohort study involved 57 children with Hp infection diagnosed by gastric endoscopy who were admitted to the Children's Hospital of Zhejiang University School of Medicine due to "abdominal pain, abdominal distension and vomiting" between January 2018 to August 2018. According to gastroscopy and pathological examination, the children were divided into chronic gastritis group and duodenal ulcer group. Gastric mucosa from Hp infected patients were sampled, and the flora DNA was analyzed by high-throughput sequencing. The statistical difference of α diversity, β diversity between two groups were analyzed. The relative abundance of the two groups in each taxonomic level was analyzed statistically. T test, Rank sum test or χ2 test was used for comparison between the two groups. Results: A total of 57 children diagnosed with Hp infection were enrolled in this study, including 42 cases of chronic gastritis (the age was (9.3±2.8) years, 22 males and 20 females) and 15 cases of duodenal ulcer (the age was (11.1±3.3) years, 9 males and 6 females). Alpha diversity index Chao and ACE in Hp infected chronic gastritis group were significantly higher than those in Hp infected duodenal ulcer group (217±50 vs. 183±64, t=2.088, P=0.009;218±47 vs. 192±76, t=1.566, P=0.016, respectively). The Beta-diversity index such as nonmetric multidimensional scaling (NMDS) analysis were significantly different in the two groups (analysis of similarity R=0.304, P=0.028). Among the main bacteria genera, there were 6 genera with significant differences between the two groups, which were Prevotella (0.190% (0.008%-1.983%) vs. 0.021% (0.005%-2.398%), Z=-2.537, P=0.011), Alloprevotella (0.097% (0.010%-0.813%) vs. 0.015% (0.003%-0.576%), Z=-2.492, P=0.013), Haemophilus (0.109% (0.004%-0.985%) vs. 0.014% (0.004%-0.356%), Z=-2.900, P=0.004), Neisseria (0.074% (0.004%-0.999%) vs. 0.024% (0.003%-0.255%), Z=-2.718, P=0.007), Streptococcus (0.166% (0.008%-1.869%) vs. 0.045% (0.006%-0.879%), Z=-2.537, P=0.010), and an unclassified-Microbacteriaceae (0.214% (0.060%-1.762%) vs. 0.117% (0.010%-0.954%), Z=-2.120, P=0.034). Linear discriminant analysis (LDA) effect sized analysis showed that at the genus level, only Prevotella was significantly enriched in the duodenal ulcer group (LDA=2.90, P=0.010), while Streptococcus, Neisseria and Haemophilus were significantly enriched in the chronic gastritis group (LDA=2.83, 2.82, 2.69, P=0.011, 0.007, 0.004, respectively). Conclusions: The gastric mucosal microbiota in duodenal ulcer associated with Hp is significantly different from that in chronic gastritis. Hp may promote the occurrence of peptic ulcer together with gastric microbiota.
目的： 探讨幽门螺杆菌（Hp）感染的慢性胃炎和十二指肠溃疡患儿胃黏膜菌群的差异。 方法： 前瞻性研究。以2018年1至8月在浙江大学医学院附属儿童医院因“腹痛、腹胀、呕吐”等症状就诊并经胃镜检查确诊为Hp感染的57例患儿为研究对象，根据胃镜下表现及病理分为慢性胃炎组及十二指肠溃疡组，提取胃黏膜菌群DNA，行高通量测序分析，比较分析两组间α多样性差异和β多样性差异，比较两组在各分类水平相对丰度变化情况。组间比较采用t检验、秩和检验或χ²检验。 结果： 57例患儿中慢性胃炎组42例［年龄（9.3±2.8）岁，男22例、女20例］、十二指肠溃疡组15例［年龄（11.1±3.3）岁，男9例、女6例］。慢性胃炎组胃黏膜菌群α多样性指数中Chao指数和ACE指数均显著高于十二指肠溃疡组（217±50比183±64，t=2.088，P=0.009；218±47比192±76，t=1.566，P=0.016），β多样性指数采用非度量多维尺度分析可显著区分两组（相似比分析R=0.304，P=0.028）。主要的菌属中慢性胃炎组和十二指肠溃疡组有6个菌属组间差异有统计学意义，分别是普雷沃菌属［0.190%（0.008%~1.983%）比0.021%（0.005%~2.398%），Z=-2.537，P=0.011］、拟普雷沃菌属［0.097%（0.010%~0.813%）比0.015%（0.003%~0.576%），Z=-2.492，P=0.013］、嗜血杆菌属［0.109%（0.004%~0.985%）比0.014%（0.004%~0.356%），Z=-2.900，P=0.004］、奈瑟菌属［0.074%（0.004%~0.999%）比0.024%（0.003%~0.255%），Z=-2.718，P=0.007］、链球菌属［0.166%（0.008%~1.869%）比0.045%（0.006%~0.879%），Z=-2.537，P=0.010］和微杆菌科的一个未分类菌属［0.214%（0.060%~1.762%）比0.117%（0.010%~0.954%），Z=-2.120，P=0.034］。线性判别分析（LDA）显示在属水平十二指肠溃疡组胃黏膜菌群只有普雷沃菌属显著富集（LDA=2.90，P=0.010），而慢性胃炎组链球菌属、奈瑟菌属及嗜血杆菌显著富集（LDA=2.83、2.82、2.79，P=0.011、0.007、0.004）。 结论： Hp感染时十二指肠溃疡组与慢性胃炎组胃黏膜菌群差异明显，Hp可能与胃黏膜菌群改变共同促进消化性溃疡的发生。.