Microbial dysbiosis shared by Crohn's disease patients and siblings

Last Updated: 2015-04-17

By Reuters Staff

NEW YORK (Reuters Health) - The siblings of patients with Crohn's disease have similar mucosal microbial dysbiosis that may contribute to the disease, researchers from UK report.

Crohn's disease patients are known to have mucosal dysbiosis, including less microbial diversity and reduced abundances of Faecalibacterium prausnitzii and Bifidobacteria, Dr. Kevin Whelan from King's College London and colleagues write in Gut, online April 8. But whether such dysbiosis is involved in the pathogenesis of the disorder is uncertain.

Siblings of Crohn's disease patients have a significantly increased risk of developing the disease, compared with the general public, and previous studies have revealed a fecal dysbiosis even in healthy siblings, the researchers add.

Since the mucosal microbiota (which requires biopsy DNA analysis) may be more important than the luminal microbiota (as reflected in the fecal microbiota), Dr. Whelan's team analyzed the mucosal microbiota of 21 Crohn's disease patients, 17 of their siblings, and 19 unrelated healthy controls.

Microbial diversity was significantly lower in both Crohn's disease patients and their siblings than in healthy controls.

Moreover, the microbial composition of Crohn's disease patients significantly differed from that of healthy controls, whereas the microbiota of siblings were not significantly divergent from that of the Crohn's disease patients or healthy controls.

F. prausnitzii was more abundant in healthy controls (accounting for 30.9% of the core species) than in Crohn's disease patients (22.4%) or their siblings (24.2%), while Escherichia fergusonii was most abundant in Crohn's disease patients (21.4%), least abundant in healthy controls (4.1%), and intermediate in siblings (9.7%).

"How and why patients and their siblings acquire the microbiota that marks out this risk is unknown," the researchers conclude. "However, knowledge of the at-risk microbial phenotype illuminates possible pathways in Crohn's disease pathogenesis and raises the prospect of intervention to impact human health and influence disease risk."

Dr. Whelan did not respond to a request for comments.

SOURCE: http://bit.ly/1zodtkx

Gut 2015.