Review article: the gut microbiome in inflammatory bowel diseaseavenues for microbial management

BackgroundThe concept of an altered collective gut microbiota rather than identification of a single culprit is possibly the most significant development in inflammatory bowel disease research. We have entered the omics era, which now allows us to undertake large-scale/high-throughput microbiota analysis which may well define how we approach diagnosis and treatment of inflammatory bowel disease (IBD) in the future, with a strong steer towards personalised therapeutics. AimTo assess current epidemiological, experimental and clinical evidence of the current status of knowledge relating to the gut microbiome, and its role in IBD, with emphasis on reviewing the evidence relating to microbial therapeutics and future microbiome modulating therapeutics. MethodsA Medline search including items intestinal microbiota/microbiome', inflammatory bowel disease', ulcerative colitis', Crohn's disease', faecal microbial transplantation', dietary manipulation' was performed. ResultsDisease remission and relapse are associated with microbial changes in both mucosal and luminal samples. In particular, a loss of species richness in Crohn's disease has been widely observed. Existing therapeutic approaches broadly fall into 3 categories, namely: accession, reduction or indirect modulation of the microbiome. In terms of microbial therapeutics, faecal microbial transplantation appears to hold the most promise; however, differences in study design/methodology mean it is currently challenging to elegantly translate results into clinical practice. ConclusionsExisting approaches to modulate the gut microbiome are relatively unrefined. Looking forward, the future of microbiome-modulating therapeutics looks bright with several novel strategies/technologies on the horizon. Taken collectively, it is clear that ignoring the microbiome in IBD is not an option.