It has been suggested that the type of stewardship intervention that is most effective fits the specific needs and resources of an institution.14,15 And although the IDSA does not recommend education as a stand-alone intervention,16 we found it to be an effective intervention for our clinicians in our work environment. However, since the CPOE guidance was in place during the educational study periods, it is possible that the effect was due to a combination of these 2 approaches. Our pre-intervention ASB treatment rates were consistent with a recent meta-analysis in which the rate of inappropriate treatment of ASB was 45%.17 This meta-analysis found educational and organizational interventions led to a mean absolute risk reduction of 33%. After the education intervention, we saw a 7% decrease in unnecessary treatment of ASB compared to baseline, and a 13% decrease compared to the month just prior to the educational intervention.
Lessons learned from our work included how clear review of local processes can inform quality improvement interventions. For instance, we initially hypothesized that IM clinicians would benefit from point-of-care CDS guidance, but such guidance used alone without educational interventions was not supported by the results. We also determined that the majority of UCs from patients on general medicine units were ordered by ED providers. This revealed an opportunity to implement similar interventions in the ED, as this was the initial point of contact for many of these patients.
As with any clinical intervention, the anticipated benefits should be weighed against potential harm. Using counterbalance measures, we found there was minimal risk in the occurrence of UTI, pyelonephritis, or sepsis if clinicians avoided treating ASB. This finding is consistent with IDSA guideline recommendations and other studies that suggest that withholding treatment for asymptomatic bacteriuria does not lead to worse outcomes.1
This study has several limitations. Data were obtained through review of the electronic health record and therefore documentation may be incomplete. Also, antimicrobials for empiric coverage or treatment for other infections (eg, pneumonia, sepsis) may have confounded our results, as empirical antimicrobials were given to 27% to 45% of patients prior to UC. This was a quality improvement project carried out over defined time intervals, and thus our sample size was limited and not adequately powered to show statistical significance. Additionally, given the bundling of interventions, it is difficult to determine the impact of each intervention independently. Although CDS for UC ordering may not have influenced ordering, it is possible that the IT intervention raised awareness of ASB and influenced treatment practices.
Conclusion
Our work supports the principles of antibiotic stewardship as brought forth by IDSA.16 This work was the effort of a multidisciplinary team, which aligns with recommendations by Daniel and colleagues, published after our study had ended, for reducing overtreatment of ASB.14 Additionally, our study results provided valuable information for our institution. Although improvements in management of ASB were modest, the success of provider education and identification of other work areas and clinicians to target for future intervention were helpful in consideration of further studies. This work will also aid us in developing an expected effect size for future studies. We plan to provide ongoing education for IM providers as well as education in the ED to target providers who make first contact with patients admitted to inpatient services. In addition, the CPOE UC ordering screen message will continue to be used hospital-wide and will be expanded to the ED ordering system. Our interventions, experiences, and challenges may be used by other institutions to design effective antimicrobial stewardship interventions directed towards reducing rates of inappropriate ASB treatment.
Corresponding author: Prasanna P. Narayanan, PharmD, 200 First Street SW, Rochester, MN 55905; narayanan.prasanna@mayo.edu.
Financial disclosures: None.