<b><i>Clostridium difficile</i></b> Infection: A Model for Disruption of the Gut Microbiota Equilibrium

Abstract

The gut microbiota is a complex ecosystem defined by the combination of microorganisms living in the gastrointestinal tract. Its equilibrium is intimately involved in several aspects of vital process for human physiology and nutrition. Its composition changes depending on both exogenous and endogenous factors. The disruption of the gut microbiota by antibiotics often leads to an opportunistic infection by Clostridium difficile. The unbalanced intestinal microbiota promotes spore germination, growth of vegetative forms and toxin production leading to C. difficile infection, which is characterized by diarrhea and possibly pseudomembranous colitis. This nosocomial infection is a good model to understand the role of the gut microbiota in preventing the development of pathogens.

Systematic review: the effects of proton pump inhibitors on the microbiome of the digestive tract—evidence from next‐generation sequencing studies

“…The biological framework provided by the large cohort studies by Imhann et al and Jackson et al and the cross‐over trial by Freedberg et al shows partial taxonomic overlap between the microbiota of PPI users and those observed in C difficile infection. These include reduced alpha diversity, increased abundance of the class Gammaproteobacteria, the family Enterobacteriaceae and the genera Veillonella , Enterococcus , Streptococcus and Lactobacillus , along with decrease in the families Ruminococcaceae and Lachnospiraceae and the genus Bifidobacterium . Freedberg et al also identified a significant increase in KEGG pathways corresponding to Staphylococcus aureus infection and to bacterial invasion of epithelial cells, including genes for antibacterial peptides and for maintenance of epithelial integrity.…”

The Microbiome and the Epigenetics of Diabetes Mellitus

“…For example, clearance of hepatitis B virus infection requires the reestablishment of the gut microbiota. Drugs also affect the microbiome including the drugs used to treat DM2 [77]. But also in the opposite direction.…”

Clostridium difficile bacteremia: Report of two cases in French hospitals and comprehensive review of the literature

“…It may be assumed that the bowel is the primary site of clostridial colonization which may predispose C. difficile to spread by translocation or intestinal perforation [17] , [42] . Indeed, monomicrobial CDB was present as frequently as CDB associated with additional pathogens to C. difficile (30/60, [50%]), which is similar to the 50% (6/12) of Lee et al series, even if it has been reported that CDB were rather polymicrobial infections probably because of the small number of cases recorded at that time [27] , [43] , [44] , [45] .…”

“…Severe underlying diseases are also commonly mentioned as predisposing situations to CDI developing. Any factors that disturb the host-microbiota homeostasis can promote C. difficile colonization and infection [11] , [12] , [13] , [14] , [15] , [16] , [17] . The most commonly incriminated antimicrobials are cephalosporins and fluoroquinolones but all antimicrobial classes are associated with a risk of CDI and the antimicrobial stewardship programmes may play a key role in CDI prevention [18] , [19] , [20] , [21] , [22] , [23] .…”