A Comparison of Fidaxomicin and Vancomycin in Patients With CDI Receiving Antibiotics for Concurrent Infections

Inclusion criteria

• Patients 18 years of age or older with >3 unformed stools/24 hours with positive stool test for C. difficile.
• Patients receiving ≥ 1 high or medium risk antibiotic for treatment of an infection other than CDI, for an anticipated duration of ≥ 5 days from the time of enrollment.

• High risk: carbapenems, 2nd-4th generation cephalosporins, fluoroquinolones, clindamycin, and beta-lactam/beta-lactamase inhibitor combinations
• Medium risk: 1st generation cephalosporin, macrolides*, and aztreonam

• *The macrolide would be considered to be low risk if patients are receiving intermittent macrolides for prophylaxis only and not for treatment of an acute infection

Exclusion criteria

• Patients with severe-complicated disease that would compromise oral therapy (hypotenstion or shock, ileus or bowel obstruction, megacolon).
• Patients with an allergy to oral vancomycin or fidaxomicin.
• Patients anticipated to receive metronidazole after enrollment.
• Patients who already received oral vancomycin or metronidazole (either oral or intravenous) for > 24 hours within the preceding 72 hours at the time of enrollment.
• Patients anticipated to receive adjunctive C. difficile therapy (rifaxamin, nitazoxanide, tigecycline) after enrollment.
• Patients who are on laxatives before they are enrolled into the study, such as lactulose, if:

• Patients have had a recent dose adjustment;
• Baseline number of bowel movement while on laxatives is unknown.
• Number of bowel movements and/or consistency has not changed from baseline.
• Patients who have had colostomy or ileostomy
• Patients who will have colostomy or ileostomy after enrollment and before study ends
• Patients who are or will be on long-term (>12 weeks) medium or high-risk antibiotics prophylaxis after enrollment