1090. Patient Outcomes With Prevented vs. Negative Clostridium difficile Tests Using Computerized Clinical Decision Support (CCDS)

BACKGROUND: Overtesting and overdiagnosis of Clostridium difficile infection (CDI) are increasingly recognized as potentially avoidable causes for unnecessary treatment and cost. Reducing inappropriate testing through diagnostic stewardship may improve C. difficile test utilization. However, the safety of these interventions is not well understood, despite the potential risk for missed or delayed diagnosis. A computerized clinical decision support (CCDS) tool was implemented at a 619-bed tertiary care hospital as part of a multifaceted effort to reduce inappropriate C. difficile testing. The intervention was associated with reductions in tests (41%) and hospital-onset CDI events (31%). We sought to examine patient outcomes associated with the intervention. METHODS: The CCDS was designed to identify patients with a prevented test if a provider initiated the CCDS and aborted the order. Outcomes of patients with either a prevented or negative nucleic acid amplification test (NAAT) were compared retrospectively. A logistic regression model was created to evaluate the association between a prevented test attempt and serious adverse events. Patients with a subsequent positive result within 7 days of the initial trigger and those treated with CDI-effective antibiotics underwent chart review. RESULTS: Multivariate analysis of 637 cases (490 negative, 147 prevented) showed that a prevented test was not associated with the primary composite outcome (inpatient mortality or ICU-transfer) compared with a negative test (adjusted odds ratio, 0.912; 95% CI 0.513–1.571). Prevented tests were associated with shorter length of stay and similar rates of CDI-related complications. Eleven (7.5%) had a subsequent positive CDI, four within 30 minutes of the prevented test, suggesting nonsignificant delay in testing. Of the remaining seven patients, case review confirmed that five did not meet testing criteria while two met testing criteria at the time of the prevented test. No serious adverse events attributable to delayed CDI diagnoses or unjustified CDI treatment were identified by individual case review. CONCLUSION: CCDS-based diagnostic stewardship for CDI may be both a safe and effective means to reduce inappropriate testing. DISCLOSURES: All authors: No reported disclosures.