353. A Cluster of Carbapenemase-Producing Enterobacter cloacae ST171 at a Tertiary Care Center Demonstrating an Ongoing Regional Threat
Session: Poster Abstract Session: HAI: Multi Drug Resistant Gram Negatives
Thursday, October 27, 2016
Room: Poster Hall
Posters
  • IDWeek poster - PEREIRA.pdf (272.0 kB)
  • Background: Increasing prevalence of carbapenemase-producing (CP) bacteria represents an urgent public health threat. In MN and ND a clonal strain of blaKPC-3-producing E. cloacae has been reported with increasing frequency.

    Methods: Between July 2015 and February 2016, 13 carbapenem-resistant E. cloacae isolates were identified at the University of MN Medical Center (UMMC) and submitted to the MN Dept. of Health for blaKPC/blaNDM PCR; 5 blaKPC-positive isolates were further characterized by PFGE and whole genome sequencing (WGS). Medical records of patients with CP-E. cloacae were reviewed.

    Results: Five patients were hospitalized at UMMC. Patients A and B were hospitalized on the same unit 6 days apart. Patient A was hospitalized again 13 days prior to patient D, in the same room. Patients C and D were hospitalized on the same unit simultaneously. Patients C and E had previous hospitalizations in ND.

    All 5 case-isolates were sequence type ST171 and blaKPC-3-positive; 3 PFGE patterns with >90% similarity were identified (Figure). In addition, plasmid types and resistance genes were very similar between the isolates, although some differences were noted (Table). WGS showed isolates A, B, and D to be closely related with <10 SNP differences.  Isolates C and E were closely related to each other, more distantly to A, B, and D; all belonged to the clonal lineage of the major circulating strain in MN and ND.

    Conclusion: All 5 case-isolates were related, however there were some distinguishing features between the most closely related isolates (A/D, C/E) suggesting that there may not have been transmission between these patients at the time of their hospitalization at UMMC. Notably, the 2 case-isolates from ND patients were more similar than the 3 from MN. This report highlights the importance of using both epidemiological and molecular data. However, more experience with WGS and plasmid exchange is needed to fully understand the relationships revealed through molecular data.  

    Table: Characteristics of five E. cloacae ST171 isolates

    Isolate

    PFGE Pattern

    Plasmid Types

    Resistance Genes

    IncFIA (HI1)

    IncX3

    aadA1, strA, aacA4, strB, sul2, dfrA14, aac(6')Ib-cr, blaOXA-9, blaTEM-1A

    blaKPC-3

    aph(3')-Ia/Ic*

    blaSHV-12

    A

    ECL64

    X

    X

    X

    X

    B

    ECL74

    X

    X

    X

    X

    X

    X

    C

    ECL18

    X

    X

    X

    X

    X

    X

    D

    ECL64

    X

    X

    X

    X*

    E

    ECL18

    X

    X

    X

    X

     

    Edwin C Pereira, MD1, Melissa Hargreaves, PhD2, Jeana Houseman, MHSA, DLM(ASCP), CIC3, Timothy Johnson, PhD4, Ruth Lynfield, MD, FIDSA5, Paula Snippes Vagnone, MT (ASCP)2, Medora Witwer, MPH5 and Susan Kline, MD, MPH, FSHEA6, (1)Infectious Diseases and International Medicine, University of Minnesota Medical School, Minneapolis, MN, (2)Public Health Laboratory, Minnesota Department of Health, St. Paul, MN, (3)Infection Prevention, University of Minnesota Health, Minneapolis, MN, (4)University of Minnesota, Saint Paul, MN, (5)Minnesota Department of Health, St. Paul, MN, (6)Department of Medicine, Infectious Disease Division, University of Minnesota Medical School, University of Minnesota Medical Center and University of Minnesota Masonic Children's Hospital, Minneapolis, MN

    Disclosures:

    E. C. Pereira, None

    M. Hargreaves, None

    J. Houseman, None

    T. Johnson, None

    R. Lynfield, None

    P. Snippes Vagnone, None

    M. Witwer, None

    S. Kline, None

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