RE: Ectopic colonization of oral bacteria in the intestine drives Th1 induction and inflammation

Dear Editor, According to Koji A et al, several negative health outcomes, including inflammatory bowel disease can be attributed to strains of Klebsiella spp. The oral cavity may serve as a reservoir for this intestinal pathobiont able to exacerbate intestinal inflammation by inducing a Th1-driven response. Consequently, identifying members of the normal gut microbiota that can provide colonization resistance against orally derived bacteria could foster future avenues for the development of effective treatments for multidrug-resistant bacteria and chronic inflammation. In our Infectious Diseases Department, we are already applying this approach by administering to cART patients with chronic gut inflammation, a high concentration multistrain probiotic formulation containing Lactobacillus plantarum DSM24730, Streptococcus thermophilus DSM24731, Bifidobacterium breve DSM24732, L. paracasei DSM24733, L. delbrueckii subsp. bulgaricus DSM24734, L. acidophilus DSM 24735, B. long DSM24736, B. infantis DSM24737. This formulation already mentioned in the Guidelines for the prevention and treatment of pouchitis and ulcerative colitis (1) has a marked bactericidal and bacteriostatic effect against antibiotic resistant KPC-producer K. pneumoniae (Minimal Inhibitory Dilution (MID) = 1:16 ; Minimal Bactericidal Dilution (MBD) = 1:8, after 24 h of incubation. Our clinical results published in 2017 (2), have shown that this formulation improved the integrity of the gut epithelial barrier by reducing IELs density and enterocytes death via apoptosis as well as mitochondrial morphology. Not being aware of the Koji ‘s data, we did not look for an association between the observed significant improvement of the intestinal inflammation and K. pneumoniae negativization. Nethertheless, the clinical results obtained with this probiotic characterized by a marked bactericidal and bacteriostatic effect against antibiotic resistant KPC-producer K. pneumoniae offer support the hypothesis by Koji, of a possible control of the inflammation of the intestines by microbiota modifiers able to antagonize the intestinal colonization by Kelbsiella, pending specific confirmatory studies.