Inclusion/ Exclusion criteria (see Eligibility Criteria). Intervention: In the first part of the study (Study 1, V0-V1) patients will be randomized in a open-label, into two groups homogeneous for number and sex of the subjects. One group will receive a supplementation of probiotic containing Bifidobacterium breve B632 and Bifidobacterium breve BR03, 15 gtt/die (3x108 CFU/die) and one group will receive a placebo for a total of 2 months of treatment. Both group receives a Standard Diet according to routine care and practice. For patients who wants to continue the study there will be a cross-over study (study 2, V2-V3) after one month of wash-out.