Inflammatory Bowel Diseases are a type of intestinal chronic inflammation
affecting the gastrointestinal tract generally developed due to environmental
susceptibility, immune-mediated susceptibility, gene-mediated susceptibility, and gut
microbiota. These heterogeneous complex immune disorders have two subtypes
commonly known as Crohn’s Disease and Ulcerative Colitis. Most studies of gut
dysbiosis are concerned with various forms of IBD. The gut microbiome consists of up
to 100 trillion microorganisms with about 1011–1012 cells/ml density comprising
viruses, protozoa, fungi, and most abundantly different bacterial strains. Bacteria
belonging to Firmicutes, Bacteroides, Proteus, and Actinomycetes phyla are the most
dominant ones in the gut microbiome and any change in the combination can cause an
abundance of pathogenic bacteria. A dysbiosis in the gut environment regarding the
above-mentioned bacterial and other microorganism compositions may lead to
gastrointestinal inflammation leading to CD and UC. Alteration in microbiota also
causes an abundance of fungi like Candida spp. and yeast, Malassezia spp. especially
M. restricta and M. globosa in the gut, which has been linked to severe colitis and CD.
Different drug-based therapies have been used for short-term relief of symptomatic
complications in IBD for the last two decades. But to avoid the side effects due to the
chronic use of conventional drugs alternative strategies such as prebiotics, probiotics,
and synbiotics have evolved in the past few years as effective treatment regimens. In
this chapter, the abnormalities of the gut microbiome are linked with IBD, and the
mechanism of the gut microbiome associated with the disease is discussed along with
the novel therapies.
Keywords: Chron’s disease, Dysbiosis, Gut microbiota, Inflammatory Bowel Diseases, IBD therapy, Short-chain fatty acids, Ulcerative colitis.
