In a prospective cohort study of patients admitted to hospitals in Quebec and Ontario, 2.8% of patients had Clostridium difficile infection and 3.0% had asymptomatic C. difficile colonization during hospitalization. Most patients with C. difficile infection had the NAP1 strain.
Clostridium difficile is the leading cause of health care-associated infectious diarrhea. After exposure to C. difficile, some patients remain asymptomatic, whereas others have illness ranging from mild diarrhea to fulminant colitis.
• What are the risk factors for developing infection with C. difficile?
Risk factors for C. difficile infection include antibiotic use, advanced age, increased severity of underlying illness, prior hospitalization, use of feeding tubes, gastrointestinal surgery, and use of proton-pump inhibitors.
• What have outbreaks of C. difficile infection in North America been attributed to?
Outbreaks of C. difficile infection in North America and Europe have been attributed to the emergence of an epidemic strain (North American pulsed-field gel electrophoresis type 1 [NAP1]).
Morning Report Questions
Q: According to the results of this study, what percentage of patients developed health care-associated C. difficile colonization and infection during their hospitalization?
A: Colonization had occurred in 2.5% of patients at 7 days, but infection did not occur in 2.5% of patients until 14 days.
Q: What toxins are produced by C. difficile?
A: The best-described C. difficile virulence factors are toxins A and B. It was initially believed that toxin A was the most important toxin in C. difficile infection, but studies have shown that toxin B may be the more potent of the two toxins. In addition, a binary toxin encoded by two genes (cdtA and cdtB) has been described in C. difficile, but its clinical significance remains uncertain.