The bacterial intestinal microbiota plays major roles in human physiology and IBDs.
Although some data suggest a role of the fungal microbiota in IBD pathogenesis, the available data are scarce.
Professor Laurent Beaugerie and colleagues from France characterized the fecal fungal microbiota in patients with IBD.
Bacterial and fungal composition of the faecal microbiota of 235 patients with IBD and 38 healthy subjects was determined using 16S and ITS2 sequencing, respectively.
The team analyzed obtained sequences using the Qiime pipeline to assess composition and diversity.
|The mean prevalence among individual countries ranged from 1% in France to 36% in Mexico|
Bacterial and fungal taxa associated with clinical parameters were identified using multivariate association with linear models.
The team observed that fungal microbiota is skewed in IBD, with an increased Basidiomycota/Ascomycota ratio, a decreased proportion of Saccharomyces cerevisiae and an increased proportion of Candida albicans compared with healthy subjects.
The researchers also identified disease-specific alterations in diversity, indicating that a Crohn's disease-specific gut environment may favour fungi at the expense of bacteria.
The concomitant analysis of bacterial and fungal microbiota showed a dense and homogenous correlation network in healthy subjects but a dramatically unbalanced network in IBD, suggesting the existence of disease-specific inter-kingdom alterations.
Professor Beaugerie's team concludes, "Besides bacterial dysbiosis, our study identifies a distinct fungal microbiota dysbiosis in IBD characterized by alterations in biodiversity and composition."
"Moreover, we unravel here disease-specific inter-kingdom network alterations in IBD, suggesting that, beyond bacteria, fungi might also play a role in IBD pathogenesis."