Abstract：
A growing amount of evidence suggests that gut microbiota plays an important role in human health, including a possible role in the pathogenesis of rheumatic and musculoskeletal diseases (RMD). We analysed the current evidence about the role of microbiota in rheumatoid arthritis (RA), spondyloarthritis (SpA), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc). In RA, we found a general consensus regarding a reduction of diversity and a specific bacterial signature, with consistent changes according to the different ethnic and geographical areas. The major pathogenetic role in RA is recognised for P. copri, L. salivarius and Collinsella, even if findings become more heterogeneous when considering established disease. In SpA, we found a relative gut abundance of Akkermansia, Coprococcus, Ruminoccocus and a relative reduction in Bacterioides and Firmicutes spp. Human and preclinical data suggest loss of mucosal barrier, increased permeability and Th1- and Th17-mediated inflammation. Additionally, HLA-B27 seems to play a role in shaping the intestinal microbiota and the consequent inflammation. In SLE, the typical gut microbiota signature was characterised by a reduction in the Firmicutes/Bacteroidetes ratio and by enrichment of Rhodococcus, Eggerthella, Klebsiella, Prevotella, Eubacterium and Flavonifractor, even if their real pathogenic impact remains unclear. In SSc, gastrointestinal dysbiosis is well documented with an increase of pro-inflammatory species (Fusobacterium, Prevotella, Ruminococcus, Akkermansia, γ-Proteobacteria, Erwinia, Trabsulsiella, Bifidobacterium, Lactobacillus, Firmicutes and Actinobacteria) and a reduction of species as Faecalibacterium, Clostridium, Bacteroidetes and Rikenella. In conclusion, seems possible to recognise a distinct gut microbiota profile for each RMD, even if significant differences in bacterial species do exist between different studies and there is a high risk of bias due to the cross-sectional nature of such studies. Therefore longitudinal studies are needed, especially on patients with preclinical and early disease, to investigate the real role of gut microbiota in the pathogenesis of RMD.
摘要：
越来越多的证据表明，肠道菌群在人类健康中起着重要作用。包括在风湿性和肌肉骨骼疾病（RMD）的发病机理中的可能作用。我们分析了当前有关微生物群在类风湿性关节炎（RA）中的作用的证据，脊柱关节炎(SpA),系统性红斑狼疮（SLE）和系统性硬化症（SSc）。在RA中,我们发现了关于多样性减少和特定细菌特征的普遍共识，根据不同的民族和地理区域有一致的变化。在RA中的主要致病作用被公认为P.copri，唾液和科林塞拉，即使在考虑确定的疾病时发现变得更加异质性。在SpA中,我们发现了相对丰富的Akkermansia，球菌,Ruminoccocus和拟杆菌和厚壁菌种的相对减少。人体和临床前数据表明粘膜屏障丧失，通透性增加和Th1和Th17介导的炎症。此外,HLA-B27似乎在塑造肠道微生物群和随之而来的炎症中起作用。在SLE中,典型的肠道微生物群特征是厚壁菌/拟杆菌比例降低和红球菌富集，Eggerthella,克雷伯菌属,普雷沃氏菌,EubacteriumandFlavonifractor,即使它们的真正致病影响仍不清楚。在SSc中,胃肠道生态失调是有据可查的促炎物种的增加（Fusobacterium，普雷沃氏菌,Ruminococus,Akkermansia,γ-变形杆菌，Erwinia,Trabsulesiella,双歧杆菌,乳酸菌,厚壁菌和放线菌），并减少了如粪杆菌的物种，梭菌属,拟杆菌和Rikenella。总之,似乎有可能识别出每个RMD的独特肠道微生物群，即使不同研究之间确实存在细菌种类的显著差异,并且由于此类研究的横断面性质,存在较高的偏倚风险.因此，需要纵向研究，尤其是临床前和早期疾病患者，探讨肠道菌群在RMD发病机制中的作用。
