CXCL8 and clostridium difficile infection: Previous candidate gene approach of genetic predisposition of CDI has revealed a promoter polymorphism –rs4073(–251T>A) and its linkage disequilibrium SNP, rs2227306(+ 781T/C), from a pro-inflammatory cytokine, IL-8—can result in increased IL-8 production and predisposes subjects to CDI6, recurrent CDI8, or severity of CDI7.