[Clostridium-difficile-associated infections].

C. difficile is a spore-forming anaerobic enteropathogen. This bacillus is responsible for virtually all cases of pseudomembranous colitis and for 15 to 25% of cases of antibiotic-associated diarrhoea. Clostridium difficile associated-infections (CDI) have a wide range of clinical features which vary from mild uncomplicated diarrhoea to severe debilitating disease, paralytic ileus, toxic megacolon, or even perforation and sometimes death. Risk factors for CDI include age > 65 years, previous hospitalization and recent antibiotic therapy. Main virulence factors for this pathogen are toxins A and B. A third toxin, the binary toxin, has been found in up to 10% of strains from infected patients. For some years, a new hypervirulent strain has emerged. This epidemic strain belongs to PCR-ribotype 027 and is responsible for outbreaks with increased mortality and severity in North America and Europe. The most effective antibiotics for treatment are oral metronidazole and vancomycin. Control of CDI needs to prevent the emergence of CDI by minimizing the number of patients exposed to antimicrobials and to limit cross transmission.