The molecular pathogenesis of Clostridium difficile-associated disease.

Clostridium difficile-associated disease is a reemerging nosocomial disease of paramount importance not only in the United States, but most of the world as well. Recently, C. difficile-associated disease appears to be on the rise, with a parallel increase noted in its severity and extent. Although the main virulence factors, the large exotoxins known as toxin A and toxin B, have long been identified, only in the past few years has a near explosion of new information regarding the details of the toxin-mediated pathogenicity come to light. This update gives an overview of some of the more exciting and insightful reports published in the recent literature.