MetaBiom
Microbiome & Chronic Diseases

Evidence Based Medicine

Crohn's disease {40000108}

Record Keys


Definition:
Crohn's disease
Class:[  ]

Details


Other Terms:
Regional Enteritis, Granulomatous Ileitis, Granulomatous Ileocolitis
Authoring date:
2019-05-15

Links


Meta Information


ICD:[  ]
Category:
Gastroenterologic
MedDra ID:
10011401
MedDra Level:
4

Notes


- In Crohn’s disease, the modules increased in the microbiome of cases include degradation of glycosaminoglycans (M00076, M00077, M00078, and M00079) and B-vitamin biosynthesis (M00122, M00123, and M00573). There is a decrease in abundance of modules associated with methanogenesis (M00576), antimicrobial peptide response (M00470), and phosphatidylethanolamine biosynthesis (M00092). (1)

- Prior use of antibiotics was associated with a nearly 2 times increased risk of developing IBD compared with no prior use. (2)

- Patients with Crohns disease showed significantly higher levels of the fungus Candida tropicalis and the bacteria Escherichia coli and Serratia marcescens than their healthy relatives. These three organisms interacted in a strategic way to form robust, pathogenic biofilms capable of driving intestinal inflammation (4)

- Electron microscopy showed that E. coli fuse to the C. tropicalis growths. Meanwhile S. marcescens make protein strings that somehow stabilize the biofilm. (5)

- Patients with Crohn NULLs disease showed significantly higher levels of the fungus Candida tropicalis and the bacteria Escherichia coli and Serratia marcescens than their healthy relatives. Further in vitro studies showed that these three organisms interacted "in a strategic way" to form robust, pathogenic biofilms capable of driving intestinal inflammation. (6)

- Patients with Crohn's disease showed significantly higher levels of the fungus Candida tropicalis and the bacteria Escherichia coli and Serratia marcescens than their healthy relatives. Further in vitro studies showed that these three organisms interacted "in a strategic way" to form robust, pathogenic biofilms capable of driving intestinal inflammation. (13)


Shared Notes


  • [1.56
    - Comprehensive overview of functional dysbiosis in the gut microbiome during IBD activity showed increases in facultative anaerobes, such as E. coli which correlates with inflammation status, and decreases in obligate anaerobes, such as Faecalibacterium prausnitzii and Roseburia hominis
    -The results of the present study confirmed decreases in the abundance of Firmicutes and Bacteroidetes, increases in Enterobacteriaceae, Pasteurellaceae, and Veillonellaceae and the presence of Fusobacterium in stool samples of CD patients.
    - Butyrate-producing bacteria are depleted in IBD patients, and probiotic treatment with these bacteria has therapeutic potential.
    - A higher proportion of Lachnospiraceae in donor stool was associated with a higher success rate of FMT [85], and recipients that responded to FMT exhibited increases in butyrate-producing Lachnospiraceae and Ruminococcaceae.
    - The reduced SCFA levels in patients with IBD result from lower abundance of SCFA-producing bacteria, especially those of the phylum Firmicutes.
  • [1.57
    - Notably, taxonomic perturbations during dysbiosis mirrored those previously observed cross-sectionally in IBD6, such as the depletion of obligate anaerobes including Faecalibacterium prausnitzii and Roseburia hominis in CD and the enrichment of facultative anaerobes such as E. coli.
    - depletion of obligate anaerobes including Faecalibacterium prausnitzii and Roseburia hominis in CD and the enrichment of facultative anaerobes such as E. coli.
    - The reduction in butyrate in particular is consistent with the previously observed depletion of butyrate producers such as F. prausnitzii and R. hominis, which was also observed here.- depletion of obligate anaerobes including Faecalibacterium prausnitzii and Roseburia hominis in CD and the enrichment of facultative anaerobes such as E. coli
    - The reduction in butyrate in particular is consistent with the previously observed depletion of butyrate producers such as F. prausnitzii and R. hominis, which was also observed here.
  • [1.58
    - Significantly lower abundances of Coprococcus in CD, Dialister in MS, and Roseburia in RA.
  • [1.59
    - the aggregated relative abundance of Klebsiella species was significantly higher in patients with Crohn NULLs disease and primary sclerosing cholangitis when compared with healthy controls. In addition, several genes that have been previously reported to be increased in the faecal microbiomes of patients with inflammatory bowel diseases -genes that include hemolysin-coregulated protein and enzymes involved in fructose-, galactitol-, mannose-, and long-chain fatty acid-related uptake and metabolic pathways- were enriched in most faecal samples of the patients with inflammatory disease who carried Klebsiella species.
    - The common skin resident fungus Malassezia restricta, is also linked to the presence of an IBD-associated polymorphism in the gene for CARD9, a signaling adaptor important for anti-fungal defense. M. restricta elicits innate inflammatory responses largely through CARD9 and is recognized by Crohn NULLs disease patient anti-fungal antibodies. This yeast elicits strong inflammatory cytokine production from innate cells harboring the IBD-linked polymorphism in CARD9 and exacerbates colitis via CARD9 in mouse models of disease.
  • [1.60
    - Probiotic treatment with butyrate-producing bacteria has therapeutic potential since these bacteria are depleted in IBD patients and butyrate has beneficial effects on epithelial barrier function and overall gut health.
  • [1.61
    - Bacteroides vulgatus is both directly associated with Th17 immunity and has a higher abundance in active CD relative to non-IBD controls.
    - The increase of Bacteroides vulgatus abundance in active CD can induce more Th17 cells that in turn might worsen IBD inflammation.

Common References