Specific risk factors for Clostridium difficile-associated diarrhea: A prospective, multicenter, case control evaluation

The severity of illness of the cases was classified as more severe than the controls, but no significant differences in antibiotic use were identified between the groups. The negative C difficile toxin studies on the well-matched control patients indicate a different etiology of diarrhea (such as antibiotic-associated diarrhea), which may have developed in the presence of similar antibiotic use as the cases.