title: Infectious etiopathogenesis of Crohn's disease.
abstract: Important advances during the last decade have been made in understanding the complex etiopathogenesis of Crohn's disease (CD). While many gaps in our knowledge still exist, it has been suggested that the etiology of CD is multifactorial including genetic, environmental and infectious factors. The most widely accepted theory states that CD is caused by an aggressive immune response to infectious agents in genetically predisposed individuals. The rise of genome-wide association studies allowed the identification of loci and genetic variants in several components of host innate and adaptive immune responses to microorganisms in the gut, highlighting an implication of intestinal microbiota in CD etiology. Moreover, numerous independent studies reported a dysbiosis, i.e., a modification of intestinal microbiota composition, with an imbalance between the abundance of beneficial and harmful bacteria. Although microorganisms including viruses, yeasts, fungi and bacteria have been postulated as potential CD pathogens, based on epidemiological, clinicopathological, genetic and experimental evidence, their precise role in this disease is not clearly defined. This review summarizes the current knowledge of the infectious agents associated with an increased risk of developing CD. Therapeutic approaches to modulate the intestinal dysbiosis and to target the putative CD-associated pathogens, as well as their potential mechanisms of action are also discussed.
authors.affiliation: Jessica Carrière, Arlette Darfeuille-Michaud, Hang Thi Thu Nguyen, Clermont Université, M2iSH, UMR 1071 Inserm/University of Auvergne, 63001 Clermont-Ferrand, France.
authors.forename: Jessica
authors.initials: J
authors.lastname: Carrière
authors.affiliation: Jessica Carrière, Arlette Darfeuille-Michaud, Hang Thi Thu Nguyen, Clermont Université, M2iSH, UMR 1071 Inserm/University of Auvergne, 63001 Clermont-Ferrand, France.
authors.forename: Arlette
authors.initials: A
authors.lastname: Darfeuille-Michaud
authors.affiliation: Jessica Carrière, Arlette Darfeuille-Michaud, Hang Thi Thu Nguyen, Clermont Université, M2iSH, UMR 1071 Inserm/University of Auvergne, 63001 Clermont-Ferrand, France.
authors.forename: Hang Thi Thu
authors.initials: HT
authors.lastname: Nguyen
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development* / Q000276:immunology; D003424:Crohn Disease / Q000175:diagnosis / Q000235:genetics / Q000276:immunology / Q000382:microbiology* / Q000628:therapy; D064806:Dysbiosis; D054884:Host-Pathogen Interactions; D006801:Humans; D007422:Intestines / Q000276:immunology / Q000382:microbiology*; D064307:Microbiota; D019936:Probiotics / Q000627:therapeutic use; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents
keywords: Adherent-invasive Escherichia coli; Antibiotics; Crohn’s disease; Dysbiosis; Fecal microbiota transplantation; Intestinal microbiota; Probiotics