What is the cause of pseudomembranous colitis?

Abnormal bacteria: ...Build up in the colon with bad bacteria clostridium difficele forming. Usually occurs after exposure to antibiotics that reduce your normal colon bacteria. Toxin is produced that damages the lining of the colon with resulting abdomen cramping pains & diarrhea, sometimes fever.

C difficile : The C. difficile bacteria tends to overgrow in certain instances, such as when one gets antibiotics that select out for the bacteria. Other risks include being in environments in which the bacteria is prevalent (like nursing homes or hospitals). The toxin made by the bacteria results in the formation of pseudomembranes in the colon.