Evolution of Intestinal Microbiota in Patients With Juvenile Spondylarthropathy According to Typology of Treatment

Descriptive Study on the Evolution of Intestinal Microbiota Profiles in Patients With Juvenile Spondylarthropathy According to the Typology of Treatment and Response to it: A Descriptive, Prospective Pilot Study

Idiopathic juvenile arthritis includes 20% of patients with arthritis with enthesitis or juvenile spondyloarthropathy. This is treated with anti-inflammatory drugs and then followed by biotherapy with DMARDs (Drugs Modifying the Activity of Rheumatic Disease) if the former are insufficient. Methotrexate (MTX) may also be used before these biotherapies. Recently, in adults, a particular profile of intestinal microbiota has been shown to alter the availability of MTX making it in efficient. Knowing that pediatric patients with juvenile spondyloarthropathy have an imbalance of their intestinal flora (dysbiosis) the investigators wanted to explore whether DMARDs could have a similar impact on the microbiota of these young patients and alter the response to treatment.

Inclusion Criteria:

• Patients aged over 6 and under 17 years old (included).
• Patients diagnosed with arthritis with juvenile enthesitis according to the International League of Associations for Rheumatology (ILAR) criteria.
• Patients who haven't been treated by Methotrexate or biotherapy for at least 3 months.
• Patients who haven't been treated by cortisone for over a month.
• Patients whose parents have given written informed consent.
• Patients for whom the consent form has been signed by their legal guardian.
• Patients covered by the Social Security System or benefitting from private health insurance.

Exclusion Criteria:

• Patients enrolled in another category 1 study or who have already taken part in a category 1 study within 3 months prior to inclusion.
• Patients who are within an exclusion period determined by another study.