The present invention relates to the use of bacterial strains belonging to the species Lactobacillus kefiri in paediatrics to generate and/or maintain the state of homeostasis. The present invention further relates to bacterial strains belonging to the species Lactobacillus kefiri having a high capacity to adhere to the intestinal epithelium; in particular, the present invention relates to the bacterial strains Lactobacillus kefiri LKF01 DSM 32079 LKEF and Lactobacillus kefiri LKF02 DSM 32080 for use in paediatrics. Finally, the present invention relates to a food composition, or a composition for a supplement, or a composition for a medical device, or a pharmaceutical composition (briefly all together the composition(s) of the present invention) comprising excipients and/or substances of a food or pharmaceutical grade formulation, and a mixture which comprises or, alternatively, consists of a bacterial strain selected from the group consisting of the bacterial strains belonging to the species Lactobacillus kefiri, said composition being for use in paediatrics to generate and/or maintain the state of homeostasis and for use in the preventive and/or curative treatment of inflammatory intestinal diseases, such as irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis (UC), in adult subjects, also in a chronic stage.La présente invention concerne l'utilisation de souches bactériennes appartenant à l'espèce Lactobacillus kefiri en pédiatrie pour générer et/ou maintenir l'état d'homéostasie. La présente invention concerne en outre des souches bactériennes appartenant à l'espèce Lactobacillus kefiri ayant une capacité élevée à adhérer à l'épithélium intestinal ; en particulier, la présente invention concerne les souches bactériennes Lactobacillus kefiri LKF01 DSM 32079 LKEF et Lactobacillus kefiri LKF02 DSM 32080 pour une utilisation en pédiatrie. Enfin, la présente invention concerne une composition alimentaire, ou une co