Pseudomembranous enteritis is commonly caused by the following two major categories of bacteria: 1. Clostridium difficile: This is a category of normal intestinal bacteria, which are generally present in the intestine under normal conditions. Because such bacteria are not significantly resistant to some cephalosporins and other antibiotics, these bacteria multiply and overgrow under routine use, causing pseudomembranous enteritis. 2. coagulase-positive Staphylococcus aureus: this category of cocci is generally bacteria resistant to penicillin as well as cephalosporins and other broad-spectrum antibiotics. It is also due to the ineffectiveness of high doses of antibiotics on it, resulting in its proliferation causing pseudomembranous enteritis. The main cause of pseudomembranous enteritis is mainly due to the long-term use of high-dose antibiotics, while the body’s immunity is reduced.