IL22 and clostridium difficile infection: The IL-22 story is interesting in light of more recent studies pointing to a protective role of IL-22 in CDI pathogenesis.52,53 In Hasegawa et al., a change in the complement system decreased circulation of pathogenic Enterobacteriaceae during CDI,52 while in Nagao-Kitamoto et al., IL-22 was shown to modify intestinal microbiota to prevent growth of C. difficile.