The average age of the patients in our study was 69 years. In 2009, there were 41 C. difficile cases originating from our institution; however, by the end of 2011, only 9 cases had been reported, a 75% reduction. The majority of our cases of C. difficile in 2009–2010 originated from our facility’s LTC units (Figure 2). Risk factors in the LTC population included older age (72% are > 65 years) with multiple comorbidities, exposure to frequent multiple courses of broad-spectrum antibiotics, and use of PPIs as the standard for GI prophylaxis therapy. Multiple antibiotic courses had a strong association with PPI administration in the patients who contracted CDI, while recent antibiotics and antibiotics greater than 10 days did not. Implications may include an increased risk of CDI in patients requiring multiple antibiotic courses concurrent with PPI exposure.
Infection prevention strategies were promulgated among the health care team during the study period but were not specifically targeted for quality improvement efforts. Therefore, in contrast to other studies where infection prevention measures and environmental hygiene were prominent components of a CDI prevention “bundle,” our focus was on antimicrobial stewardship and PPI and probiotic use, not enhancement of standard infection prevention and environmental hygiene measures.
The antibiotics used prior to the development of CDI in our study were similar to findings from other studies that have associated broad-spectrum antibiotics with increased susceptibility to CDI [11]. Antimicrobials disrupt the normal GI flora, which is essential for eradicating many C. difficile spores [12]. The utilization of high-risk antibiotics and prolonged antimicrobial therapy were reduced with implementation of our antimicrobial stewardship program. In 2012, the antimicrobial stewardship program developed a LTC fever protocol, providing education to LTC nurses, physicians, and pharmacists using the modified McGeer criteria [13] for infection in LTC units and empiric antibiotic recommendations from our epidemiologist. A formal recommendation for a LTC 7-day stop date for urinary, respiratory, and skin and soft tissue infections was initiated, which included are-assessment at day 6–7 for resolution of symptoms.
With regard to PPI therapy, our study revealed that patients who had received a PPI at some point were 3.05 times more likely to have a recurrence of CDI than those who had not. These findings are consistent with the literature. Linsky et al [5] found a 42% increased risk of CDI recurrence in patients receiving PPIs concurrent with CDI treatment while considering covariates that may influence the risk of recurrent CDI or exposure to PPIs. A meta-analysis of 16 observational studies involving more than 1.2 million hospitalized patients by Janarthanan et al [14] explored the association between CDI and PPIs and showed a 65% increase in the incidence of CDI among PPI users. Those receiving PPI for GI prophylaxis in the earlier time period (before 2011) were 77% more likely to have a recurrence than those who received PPI in the later period. This finding might be associated with the more appropriate antimicrobial use and the more consistent use of consistent prophylactic probiotics in the later study period.