During a consultation in the nephrology departments : the study will be presented to the patient and the information leaflet will be given to him.~During a subsequent visit, after checking the level of serum CRP and obtaining the consent of the investigating physician, a blood test will be taken to assess the intestinal permeability and the inflammatory state. A health-related quality of life (SF-36) and frailty questionnaire (previous questionnaire, MNA questionnaire; Mini Nutritional Assessment - Short Form and physical activity question) will be completed by the patient. Two faecal sampling kits (one for D0 and one for M2) will be distributed to patients.~During the D0 visit, patients will be randomized into two arms. Both arms will receive the same dietary advice. The intervention group will receive symbiotics (prebiotics: Orafti®Synergy1 and probiotics: Vivomixx®) for 8 weeks against a placebo in the control group. The treatment will begin after the collection of the first stools (kit J0).~At the end of the treatment (M2 or 56 days later), a new blood sample will be taken. Two other blood samples will be taken 4 months and 6 months after the start of treatment. Patients will also provide a faecal sample and complete the various questionnaires at the end of treatment (M2), 2 months after (M4) and 4 months after (M6) treatment.~The study will have no influence on the management of the patient. It does not require any additional consultation or any particular biological assessment other than that described. Treatments should not be influenced by the study. The samples will be processed without knowledge of the initial characteristics of the patients, nor of their evolution.
Main objective: To assess the effectiveness of treatment with symbiotics on the chronic systemic inflammation observed in chronic renal failure 4 months after the start of treatment.