The Role of Intestinal Microbiota Dysbiosis in the Development of Spondyloarthritis

As secondary objectives, the study aims:

• to research the abundance of bacterial strain of R. gnavus in mucosal sampling by biopsy;
• to study the interaction between R. gnavus bacterium and mucus from histological sampling;
• to correlate the expression of genes of intestinal mucus with the variations of identified microbiota of mucus biopsy;
• to study the interaction between bacteria and intestinal epithelial cells during culture;
• to demonstrate perturbations of the immune responses by dysbiosis.

Inclusion criteria

Patients with SPA:

• Patients ⩾ 18 years;
• Diagnosed as spondyloarthritis (SpA) according ASAS classification;
• Affiliated to a social security scheme;
• Have signed the written informed consent form.

Control subjects:

• Subjects ⩾ 18 years;
• Subjects free of SPA and planned for a digestive endoscopy for another indication such as to explore the risk of colorectal cancer in family member;
• Affiliated to a social security scheme;
• Have signed the written informed consent form.

Exclusion criteria

• Subjects unable to understand the proposed study and/or sign a informed consent form;
• Pregnant women or breast feeding women;
• Subjects under guardianship or curatorship;
• Have taken antibiotic 1 month prior to inclusion;
• Presenting acute or chronic severe pathology may likely to interfere with the interpret of outcome;
• Refusal of subjects to participate to the study;
• Foreign patients under french AME scheme.