BACKGROUND & AIMS Altering the intestinal microbiota has been proposed as a treatment for inflammatory bowel diseases (IBDs), but there are no established associations between specific microbes and IBD. We performed a systematic review to identify frequent associations. METHODS We searched the MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials databases, through April 2, 2018 for studies that compared intestinal microbiota (from fecal or colonic or ileal tissue samples) among patients (adult or pediatric) with IBD vs healthy individuals (controls). The primary outcome was difference in specific taxa in fecal or intestinal tissue samples from patients with IBD vs controls. We used the Newcastle-Ottawa scale to assess the quality of studies included in the review. RESULTS We identified 2631 citations; 48 studies from 45 articles were included in the analysis. Most studies evaluated adults with Crohn's disease or ulcerative colitis. All 3 studies of Christensenellaceae and Coriobacteriaceae and 6 of 11 studies of Faecalibacterium prausnitzii reported a decreased amount of those organisms compared with controls, whereas 2 studies each of Actinomyces, Veillonella, and Escherichia coli revealed an increased amount in patients with Crohn's disease. For patients with ulcerative colitis, Eubacterium rectale and Akkermansia were decreased in all 3 studies, whereas E coli was increased in 4 of 9 studies. The microbiota diversity was either decreased or not different in patients with IBD vs controls. Fewer than 50% of the studies stated comparable sexes and ages of cases and controls. CONCLUSIONS In a systematic review, we found evidence for differences in abundances of some bacteria in patients with IBD vs controls, but we cannot make conclusions due to inconsistent results and methods among studies. Further large-scale studies, with better methods of assessing microbe populations, are needed.

中文翻译：

---

有和没有炎症性肠病的患者肠道菌群的差异：系统评价。

背景与目的已提出改变肠道菌群作为治疗炎症性肠病（IBDs）的方法，但是在特定微生物和IBD之间尚无已建立的关联。我们进行了系统的审查，以确定频繁的关联。方法我们搜索了MEDLINE，EMBASE，Cochrane系统评价数据库和Cochrane对照试验中央注册数据库，直到2018年4月2日，以比较患者（成人或儿科）的肠道菌群（粪便，结肠或回肠组织样本） ）与IBD相比健康个体（对照组）。主要结果是IBD患者与对照组的粪便或肠组织样品中特定分类单元的差异。我们使用纽卡斯尔-渥太华量表来评估该评价中包括的研究质量。结果我们确定了2631篇被引；分析包括来自45篇文章的48个研究。大多数研究评估了患有克罗恩氏病或溃疡性结肠炎的成年人。Christensenellaceae和Coriobacteriaceae的所有3项研究以及prausnitzii的Faecalibacterium praesnitzii的11项研究中的6项均报告说，与对照相比，这些微生物的数量减少，而放线菌，Veillonella和Escherichia coli的2项研究表明，克罗恩病患者的细菌数量有所增加。对于溃疡性结肠炎患者，在全部3项研究中直肠直肠细菌和Akkermansia均减少，而在9项研究中的4例中大肠杆菌增加。与对照组相比，IBD患者的菌群多样性降低或没有差异。少于50％的研究表明病例和对照组的性别和年龄具有可比性。结论在一项系统评价中，我们发现了IBD患者与对照患者某些细菌的丰度存在差异的证据，但由于研究之间的结果和方法不一致，我们无法得出结论。需要进一步的大规模研究，并采用更好的评估微生物种群的方法。