Welcome to JA. I think you must mean Clostridium difficile, often shortened to "C. diff" in the hospital. When someone has been on strong antibiotics, their medication can kill off the "good" intestinal bacterial along with the bacteria it is being prescribed for. When that happens, Clostridium difficile, which normally inhabits everyone's colon with no problem, grows out of bounds, causing an infection. The treatment is metronidazole or vancomycin.