No Statistically Significant Difference in CDI Recurrence with Vancomycin Prophylaxis

Clostridium difficile infections (CDI) can be difficult to manage due to the association with high rates of recurrence. These recurrences are complicated in that some of the major risk factors for recurrence are previous CDI episode(s) and exposure to antibiotics. Currently, the Infectious Diseases Society of America guidelines for CDI do not take a stance on the use of secondary prophylaxis due to a lack of data.

New research conducted by a team of investigators from Michigan Medicine set out to explore if there was a connection between use of oral vancomycin for prophylaxis and a reduction in CDI recurrence. The findings of their research were presented in a poster session at the Making a Difference in Infectious Diseases 2019 (MAD-ID) annual meeting.

While previous research has suggested that vancomycin prophylaxis as led to a reduction in CDI recurrence, the studies were limited by both prescriber bias and in that the studies included all hospitalized adult patients with prior CDI who had received systematic antibiotics.

For this research, the investigators included patients over the age of 2 years who had experienced at least 2 episodes of CDI within the last year prior to exposure to broad-spectrum antibiotics. The retrospective cohort included the prophylaxis group, made up of 20 patients who received oral vancomycin for > 50% of the duration of broad-spectrum antibiotic therapy and the no prophylaxis group, comprised of 88 patients who did not receive oral vancomycin while on broad-spectrum antibiotics.

The authors indicate that baseline characteristics significantly differed between the 2 groups. These characteristics included prior transplantation (19.3% in the no prophylaxis group vs. 50% in the prophylaxis group, p=0.008), the need for tube feeds, central line, or urinary catheter during antibiotic exposure (51.5% vs. 35%, p=0.034), and receipt of carbapenems (10.2% vs. 30%, p=0.032).

The investigators compared the cohorts through univariate analysis in order to identify characteristics associated with CDI recurrence within 12 weeks. The study found that the primary outcome of CDI incidence was 13.6% within 12 weeks of broad-spectrum antibiotic initiation in the group that did not receive prophylaxis compared to the prophylaxis group with 10% within 12 weeks of discontinuing vancomycin prophylaxis (p=0.622).

Results also indicate that the average time to CDI was longer in the prophylaxis cohort compared to the group that did not receive prophylaxis (45.5 + 24.7 vs. 26.6 + 23.5 days, p=0.198). The secondary outcomes of all-cause mortality, all-cause ICU admission, length of stay, need for colectomy or diverting loop ileostomy, and documented vancomycin-resistant Enterococcus (VRE) infection and colonization were reported to be similar between the 2 groups.

The authors conclude that there was no statistically significant difference in CDI recurrence within 12 weeks between patients receiving oral vancomycin prophylaxis compared those who did not. However, the investigators note that there appeared to be a trend towards a delay in recurrence with oral vancomycin and that the study had a small number of patients in the prophylaxis cohort and a low rate of CDI events.

The poster “Oral Vancomycin for Secondary Prophylaxis of Clostridium difficile Infections Among High Risk Patients” was presented on Thursday, May 9, 2019 at MAD-ID 2019 in Orlando, Florida.