Clostridoides difficile is an intestinal pathogen responsible for 500,000 infections and 30,000 deaths annually in the US. Alarmingly, C. difficile infection is increased in patients with inflammatory bowel disease (IBD). When C. difficile infection is superimposed on colitis, it synergistically worsens both conditions. C. difficile infection is initiated by disruption of the gut microbiota; and it is well appreciated that IBD patients already have an altered fecal and mucus-associated microbiota.