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Published on: December 8, 2014
The faecal flora in ulcerative colitis
Journal of Medical Microbiology
|November 1, 1975
Summary
Patients with ulcerative colitis have increased gut bacteria, specifically group-D streptococci, and reduced bifidobacteria. These bacteria break down mucin and hyaluronic acid, potentially causing high lactic acid levels in colitis patients.
Area of Science:
- Microbiology
- Gastroenterology
- Human Gut Microbiome Research
Background:
- Ulcerative colitis (UC) is characterized by gut inflammation and dysbiosis.
- Faecal flora analysis reveals significant differences between healthy individuals and UC patients.
Purpose of the Study:
- To investigate the specific microbial changes in the faecal flora of ulcerative colitis patients.
- To explore the functional capabilities of these altered microbial communities, particularly in relation to mucin and hyaluronic acid breakdown.
Main Methods:
- Differential faecal flora counts were performed on samples from UC patients and healthy controls.
- Microbial strains were isolated and their enzymatic activities (mucin and hyaluronic acid breakdown) were assessed.
Main Results:
- UC patients exhibited a 100-fold increase in group-D streptococci and a reduction in bifidobacteria compared to healthy subjects.
- An increased variety of enterococci was observed in UC patients.
- Strains from UC patients demonstrated enhanced mucin breakdown and were uniquely capable of hyaluronic acid degradation.
- These substrates can be fermented to produce lactic acid.
Conclusions:
- The faecal flora in ulcerative colitis is characterized by a dysbiotic state with an overgrowth of specific streptococcal and enterococcal strains.
- The enhanced ability of these bacteria to degrade mucin and hyaluronic acid may contribute to the high lactic acid levels observed in UC patients.
- These findings suggest a potential role for these microbial activities in the pathogenesis or exacerbation of ulcerative colitis.
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