On the other hand, IL-23 (21, 22), IL-17A (23, 24), Toll-like receptor 2-mediated signaling (16), chemokine (C-X-C motif) ligand 5 (CXCL-5) (25), IL-6 (23), IL-8 and C-C motif chemokine ligand 5 (CCL5) (26) were associated with unfavorable outcome during CDI. This evidence concerns the gene CXCL8 and clostridium difficile infection.