Clostridioides difficile associated diseases (CDAD) are the most frequently identified causes of nosocomial diarrhoea and the most important diarrhoeal disease of inpatients (about 20 to 40 % of hospital patients are colonized with C. difficile) in Germany.
Clostridioides difficile is a spore- and toxin-forming Gram-positive rod bacterium, which is one of the bacteria found in the intestinal flora of 3% of healthy adults. It is much more common in infants, but rarely causes problems.
The outbreak of a disease or proliferation of the bacterium is usually the result of a disturbance of the intestinal flora, whether through antibiotic treatment, colonoscopy or other interventions, by which competing types of normal intestinal colonisation are suppressed. As a consequence of this altered intestinal flora, C. difficile can proliferate and produce and release toxins (toxins A and B) that damage the intestinal wall, causing infectious diarrhoea (Clostridioides difficile infection, abbreviation CDI) and possibly leading to life-threatening pseudomembranous colitis.
The bacterium with high environmental resistance (spores insensitive to heat and many disinfectants) is transmissible from person to person. Over 80% of the reported diseases occur in the older generation (> 65 years).