Clostridium difficile was discovered in 1935 as part of the normal colonic flora of newborn infants. It inhabits the gut of up to 70% of healthy newborns and 3% of healthy adults, so it hasn't always been considered a pathogen. The microbe's destructive nature emerged only after the use of broad-spectrum antibiotics came into vogue. The bacterium is also found in the intestines of other mammals and fish, mammalian feces, and soils. It is a member of the bacteria family that produces exotoxins that cause tetanus and botulism, as well as other diseases.

     Though it is sometimes misdiagnosed, as unspecified intestinal infections, Clostridim difficile is responsible for nearly all gastrointestinal infections, ranging from mild diarrhea to severe or even fatal colitis. that follow antibiotic therapy. in the USA it affects approximately 3 million people yearly. Patients taking antibiotics are at risk of becoming infected with C. difficile. Antibiotics disrupt the normal bacteria of the bowel, allowing c. fifficile bacteria to become established in the colon. Many persons infected with C. difficile have no symptoms. These people become carriers of the bacteria and can infect others. In other people, a toxin procuced by C.diffiicle damages the gut wall, causing many problems.

     People who are severely affected can develpoe a case so bad its called , Pseudomembranous colitis, which is caused by overgrowth of organism in the colon after normal flora is disturbed by antimicrobial therapy. The organism produces toxins that are lethal to the intestinal epithelium that cause small patches (psuedomembranes) of cell debris, inflammatory cells and clotted serum to form on the colon's lining. Rarely, the walls of the colon wear away and holes develop (colon perforation), which lead to a life-threatening infection of the abdomen.