330. Molecular Epidemiology and Outcomes of Carbapenem Non-Susceptible (CARB-NS) Clinical Isolates in Detroit
Session: Poster Abstract Session: HAI: Multi Drug Resistant Gram Negatives
Thursday, October 27, 2016
Room: Poster Hall
  • veve_molEpi_outcomes.pdf (284.3 kB)
  • Background: The emergence and spread of carbapenem resistant organisms is a significant burden to healthcare systems worldwide. We describe the molecular bla identified in carbapenem non-susceptible (CARB-NS) isolates found in our institution and the characteristics of infected patients.

    Methods: A cohort of CARB-NS clinical blood, urine, respiratory tract and other isolates were evaluated from 1/2013 to 12/2015. Whole genomic DNA from CARB-NS Enterobacteriaceae (EB) and Pseudomonas sp. (PS) was purified before undergoing real-time polymerase chain reaction using SYBR Green (Bio-Rad). Primers and control organisms (CDC, Georgia) for bla sequences (NDM, KPC, VIM, SME, GES, IMP) were confirmed using melt-curve analyses relative to control organisms. Patient characteristics, treatment and outcomes were extracted from electronic medical records using a standardized case report form.

    Results: 161 isolates were screened for carbapenemase production; EB 90 (56%), PS 71 (44%). 55 (34%) were found to harbor blaKPC (EB 50, 91%; PS 5, 9%). All other bla tested were non-confirmatory. Of unique isolates, variables independently associated with blaKPC were: male sex (OR, 0.3; 95% CI, 0.13-0.71), active hematological disease (OR, 3.3; 95% CI, 1.2-8.9), as seen in Table 1. Previous 5-year history of ESBL or CRE was not associated with blaKPC . Of 43 unique patients with confirmed blaKPC, 28 (65%) were treated with systemic antibiotics. The most common infection sites were: bloodstream (50%), urinary tract (25%). 50% of patients had multiple infection sites. Most common organisms causing infection were: K. pneumonia (56%) and E. coli (14%). For all non-urinary tract infections, monotherapywas employed more frequently than combination therapy for both initial (68% vs. 32%) and definitive treatment (56% vs. 44%). 6-month all-cause mortality for treated patients was 57%.

    Conclusion: Carbapenemase production was not frequently identified in CARB-NS isolates, but the predominate bla­-sequence was KPC. Treatment regimens varied widely. An understanding of CARB-NS regional genomic sequencing is beneficial for clinicians to target appropriate antibiotic therapy and improve infection control procedures.

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    Michael Veve, PharmD1, Jeremy Delor, PharmD student2, Robert Tibbetts, Ph.D. D(ABMM), F(CCM)3 and Susan L Davis, PharmD1, (1)Wayne State University College of Pharmacy, Detroit, MI, (2)Henry Ford Hospital, Detroit, MI, (3)Pathology and Microbiology, Henry Ford Hospital, Detroit, MI


    M. Veve, None

    J. Delor, None

    R. Tibbetts, None

    S. L. Davis, None

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.