AbstractBackgroundCurrent approaches in tracking Clostridioides difficile infection (CDI) and individualizing patient management are incompletely defined.MethodsWe recruited 468 subjects with CDI at Mayo Clinic Rochester between May and December 2016 and performed whole-genome sequencing (WGS) on C. difficile isolates from 397. WGS was also performed on isolates from a subset of the subjects at the time of a recurrence of infection. The sequence data were analyzed by determining core genome multilocus sequence type (cgMLST), with isolates grouped by allelic differences and the predicted ribotype.ResultsThere were no correlations between C. difficile isolates based either on cgMLST or ribotype groupings and CDI outcome. An epidemiologic assessment of hospitalized subjects harboring C. difficile isolates with ≤2 allelic differences, based on standard infection prevention and control assessment, revealed no evidence of person-to-person transmission. Interestingly, community-acquired CDI subjects in 40% of groups with ≤2 allelic differences resided within the same zip code. Among 18 subjects clinically classified as having recurrent CDI, WGS revealed 14 with initial and subsequent isolates differing by ≤2 allelic differences, suggesting a relapse of infection with the same initial strain, and 4 with isolates differing by >50 allelic differences, suggesting reinfection. Among the 5 subjects classified as having a reinfection based on the timing of recurrence, 3 had isolates with ≤2 allelic differences between them, suggesting a relapse, and 2 had isolates differing by >50 allelic differences, suggesting reinfection.ConclusionsOur findings point to potential transmission of C. difficile in the community. WGS better differentiates relapse from reinfection than do definitions based on the timing of recurrence.
1077. Reduce Anti-Microbial Use in Extracorporeal Membrane Oxygenation: Reduce AMMO Study
Abstract Background The use of extracorporeal membrane oxygenation (ECMO) in critically ill adults is increasing. Patients on ECMO are at high risk for infections, with 20.5% of adults acquiring infections while on ECMO. An Extracorporeal Life Support Organization (ELSO) Infectious Disease Task Force statement concluded that no antibiotic prophylaxis is needed for patients on ECMO though it also noted that this was based on limited data. We implemented an antimicrobial prophylaxis protocol for patients on ECMO at our institution and analyzed antimicrobial use and outcomes in these patients with a pre- and post-analysis. Methods We conducted a retrospective review of 294 patients on ECMO between July 1, 2011 and July 1, 2017. An ECMO antimicrobial prophylaxis guideline was initially implemented on July 1, 2014; there was poor adherence to the guideline and antimicrobial use actually increased. A more restrictive protocol was implemented in November 2018 with input from stakeholders including cardiac surgeons, critical care and infectious disease (ID) providers. We had a cohort of 161 patients before (July 2014–November 2018) and 37 patients after (November 2018–April 2018) the implementation of the updated protocol. We evaluated primary outcomes of gross days of antimicrobial use, percent of antibiotic-free days and days of individual antimicrobial use, adjusted for APACHE scores and ECMO duration. Results When adjusted for days on ECMO, mean antibiotic days decreased after implementation of the protocol; for vancomycin (0.27 vs. 0.02, P < 0.0003), cefepime (0.15 vs. 0.02, P < 0.02), meropenem (0.09 vs. 0, P < 0.02), zosyn (0.16 vs. 0, P < 0.002), caspofungin (0.346, 0.138 P < 0.003). This was accompanied by a nonsignificant increase in mean fluconazole use (0.29 vs. 0.37, P < 0.3). There was no impact on patient mortality or nosocomial infection rate. Additional results can be found in table. Conclusion The use of an antimicrobial prophylaxis protocol in ECMO patients led to improvement in antimicrobial usage without increasing nosocomial infections in a population at a high risk of infection. Disclosures All authors: No reported disclosures.
250. Antimicrobial Management in Extracorporeal Membrane Oxygenation: The AMMO study
Objective: To characterize agreement in the ascertainment of surgical site infections (SSIs) between the National Surgical Quality Improvement Program (NSQIP), National Healthcare Safety Network (NHSN), and administrative data. Background: The NSQIP, NHSN, and administrative data are the primary systems used to monitor and report SSIs for the purpose of quality control and benchmarking of hospitals and surgeons. These systems have different methods for identifying SSIs. Methods: We queried the NHSN, NSQIP, and administrative data systems for patients who had an operation at 1 of 4 hospitals within a single health system between January 2013 and September 2015. The detection of an SSI during a postoperative hospitalization was the outcome of analysis. Any SSI detected by one (or more) of these systems was analyzed by 2 reviewers to determine the presence of discrete elements of documentation constituting evidence of SSI. Concordance between the 3 systems (NHSN, NSQIP, and administrative data) was analyzed using Cohen's kappa. Results: After application of appropriate exclusion criteria, a cohort of 9447 inpatient operations was analyzed. In total, 130 SSIs were detected by 1 or more of the 3 systems, with reported SSI rates of 0.5% (NHSN), 0.7% (administrative data), and 1.0% (NSQIP). Of these 130 SSIs, only 17 SSIs were reported by all 3 systems. The concordance between these 3 systems was moderate (kappa values NSQIP-NHSN = 0.50 [0.40–0.60], administrative-NHSN = 0.36 [0.24–0.47], and administrative-NSQIP = 0.47 [0.38–0.57]). Chart review found that reasons for discordance were related to issues of different criteria as well as inaccuracies. Conclusion: There is significant discordance in the determination of SSIs reported by the NHSN, NSQIP, and administrative data. The differences and limitations of each of these systems have to be recognized, especially when using these data for quality reports and pay for performance.
Methicillin-Resistant Staphylococcus aureus Infection in ICU: What Is the Best Prevention Strategy?*
Abstract Ten case reports of disseminated Mycobacterium chimaera infections associated with cardiovascular surgery were published from Europe. We report 3 cases of disseminated M chimaera infections with histories of aortic graft and/or valvular surgery within the United States. Two of 3 patients demonstrated ocular involvement, a potentially important clinical finding.
Automating Quality Metrics in the Era of Electronic Medical Records: Digital Signatures for Ventilator Bundle Compliance
Ventilator-associated events (VAEs) are associated with increased risk of poor outcomes, including death. Bundle practices including thromboembolism prophylaxis, stress ulcer prophylaxis, oral care, and daily sedation breaks and spontaneous breathing trials aim to reduce rates of VAEs and are endorsed as quality metrics in the intensive care units. We sought to create electronic search algorithms (digital signatures) to evaluate compliance with ventilator bundle components as the first step in a larger project evaluating the ventilator bundle effect on VAE. We developed digital signatures of bundle compliance using a retrospective cohort of 542 ICU patients from 2010 for derivation and validation and testing of signature accuracy from a cohort of random 100 patients from 2012. Accuracy was evaluated against manual chart review. Overall, digital signatures performed well, with median sensitivity of 100% (range, 94.4%–100%) and median specificity of 100% (range, 100%–99.8%). Automated ascertainment from electronic medical records accurately assesses ventilator bundle compliance and can be used for quality reporting and research in VAE.