Cucchiara Salvatore, Iebba Valerio, Conte Maria Pia, Schippa Serena
Pediatric Gastroenterology and Liver Unit, Department of Pediatrics, Sapienza University of Rome, IT-00161 Rome, Italy.
Dig Dis. 2009;27(3):252-8. doi: 10.1159/000228558. Epub 2009 Sep 24.
Many efforts were made in the past decades to assess the role of gut microbiota in inflammatory bowel diseases (IBD), leading to the hypothesis that an altered microbial composition, other than the presence of a specific pathogen, could be involved in the pathogenesis of the disease. On the other hand, existing differences in gut microbial community between distinct classes of age make sense of an increasing research in microbial shifts in IBD.
Cultural, molecular, metabolomic and metagenomic approaches are trying to define the human gut microbiota in different age groups.
An increase in anaerobic bacteria (Bacteroidesvulgatus, Streptococcus faecalis) was observed in adult IBD, whereas an increase in aerobic and facultative-anaerobic (Escherichia coli) was found in pediatric IBD. Overall higher bacterial cell counts were observed in IBD, jointly with a general loss of biodiversity and a preponderance of Bacteroidetes and a parallel decrease of Firmicutes phylum: a predominance of potential harmful members of Proteobacteria (E. coli) and low abundance of beneficial species (Faecalibacterium prausnitzii) was also reported in pediatric and adult age groups, respectively. Microbial community of elderly subjects contains a wider range of different species than those of children and adults, both in healthy and IBD status.
在过去几十年里，人们为评估肠道微生物群在炎症性肠病（IBD）中的作用付出了诸多努力，由此产生了一种假说，即除特定病原体的存在外，微生物组成的改变可能参与了该疾病的发病机制。另一方面，不同年龄组之间肠道微生物群落存在的差异使得对IBD中微生物变化的研究日益增多。
培养、分子、代谢组学和宏基因组学方法正试图界定不同年龄组的人类肠道微生物群。
在成年IBD患者中观察到厌氧菌（脆弱拟杆菌、粪肠球菌）增加，而在儿童IBD患者中发现需氧菌和兼性厌氧菌（大肠杆菌）增加。总体而言，在IBD患者中观察到细菌细胞计数更高，同时生物多样性普遍丧失，拟杆菌门占优势，厚壁菌门平行减少：在儿童和成人年龄组中分别还报告了变形菌门潜在有害成员（大肠杆菌）占优势和有益物种（普拉梭菌）丰度低的情况。无论健康与否，老年受试者的微生物群落比儿童和成人包含更广泛的不同物种。
