For this second day, various talks were about gut microbiome in diseases. Here we report the take home messages:


Qin Nan, who worked with Pr. Lanjuan Li‘s team, studied H7N9 virus outbreak through its impact on the gut microbiota. They observed using a metagenomic approaches that diversity decreased with virus infection compared to healthy people.

James Versalovic presented studies related to Irritable Bowel Syndrom (IBS) in children. Microbial composition of children with IBS clustered together. However, subtypes of IBS did not correlate with microbial composition. One of the subtypes of IBS patients is healthy-like microbiota. IBS microbiota seems to be enriched for methane metabolism but depleted for pyruvate metabolism.

Phillip Tarr studied microbiota of premature infants. He reminded us that microbial richness increases through life from birth to adult. In case of necrosis enterocolitis, Gammaproteobacteria increase in premature microbiota. Studying 1020 samples from premature babies day by day, he observed a high temporal variation in microbial composition. During this variation, three microbial states were observed: a Bacilli enriched, a Gammaproteobacteria enriched and a Clostriales enriched microbiome. Main driver of those changes were gestational age and day of life.

Jeroen Raes presented us his recent work on fecal transplantation. While it worked successfully in C. difficile infection there are many open questions remaining for this technical intervention. It is important for example to establish some guidelines for the donor. Clinical studies on this area are difficult to design because of ethics. Studying microbiota during fecal transplantation will be one way to overcome some issues. First results showed that microbial temporal stability increases chance for a positive response for patient with ulcerative colitis. This first observation opened new perspectives in this area. However, stability is not associated with chances of success in Crohn’s disease context.