 The primary outcome is recurrent CDI definite or probable or death within 56 days of randomization. Definite recurrence is defined as: new onset of more than 3 loose or watery stools in 24 hours for 2 consecutive days with laboratory confirmation of C. difficile from a stool specimen; or ileus, toxic megacolon or colectomy with laboratory confirmation. Probable recurrence is defined identically as above but WITHOUT laboratory confirmation of C. difficile not tested or negative test. 