Clostridioides difficile (previously known as Clostridium difficile) causes antibiotic-associated diarrhea (AAD) and pseudomembranous colitis (PMC), an inflammatory colon disease caused by C. difficile toxins.
C. difficile produces two potent toxins:
- Toxin A (TcdA), an enterotoxin
- Toxin B (TcdB), a cytotoxin
The production of these toxins in the gastrointestinal tract ultimately leads to disease. There is a relationship between toxin levels, pseudomembranous colitis (PMC) development, and the duration of diarrhea.
For years, toxin A was considered more important than toxin B in the disease process. Later on, disease-producing strains producing only toxin B were identified. These strains produced severe disease, and toxin B was found to be responsible for more severe damage to intestinal cells.
