374. Temporal trends in Ceftriaxone resistant Escherichia coli infections
Session: Poster Abstract Session: HAI: Multi Drug Resistant Gram Negatives
Thursday, October 27, 2016
Room: Poster Hall
Posters
  • 374, IDWEEK 2016.pdf (310.4 kB)
  • Background: Recent reports of community acquired infections caused by extended spectrum beta-lactamase (ESBL) producing E. coli infections signal a worrisome trend. Using ceftriaxone resistance as a surrogate marker for ESBL production, this study describes trends in ceftriaxone resistant E. coli (EC-CTxR) isolates in urine & blood cultures in our health care system over a 10 year time period.

    Methods: Kaiser Permanente Northern California (KPNC) is an integrated health care delivery system providing care to approximately 3.3 million members. A network of 49 medical clinics and 19 hospitals are served by a centralized regional microbiological laboratory & an electronic medical record system. Databases were queried for the time period between Jan 1, 2004 to Dec 31, 2013 to obtain relevant information. For each individual, we included only those isolates not preceded by another isolate from the same source in the prior 365 days. Infection rates were calculated per 100,000 member-years & adjusted for 2013 KPNC membership.

    Cases were classified into 3 mutually exclusive groups:

    Healthcare-associated, hospital-onset (HCA-HO)

    Healthcare-associated, community-onset (HCA-CO)

    Community-associated (CA)

    Results: For EC-CTxR bloodstream infections, rates for CA onset cases increased 10-fold from 0.13 to 1.44 cases per 100,000 member years. Rates for HCA-CO infections increased by 3.5-fold from 0.51 to 2.27 cases per 100,000 member years. Rates for HCA-CO infections were stable from 0.25 to 0.28 cases per 100,000 member years. For EC-CTxR urinary isolates, rates for CA onset cases increased 4.5-fold from 5.75 to 32.30 cases per 100,000 member years. Rates for HCA-CO cases increased by 3-fold from 4.42 to 18.83 cases per 100,000 member years. Rates for HCA-HO cases were stable from 1.06 to 1.5 cases per 100,000 member years. Rates of ceftriaxone susceptible E coli isolates were stable from 43.33 cases to 45.39 cases per 100,000 member years for blood isolates and 1227.25 to 1460.59 cases per 100,000 member years for urine isolates.

    Conclusion: EC-CTxR isolates in urine increased significantly over the study period. For EC-CTxR blood isolates, relative rates increased significantly but absolute rates remained low.

    Sumanth Rajagopal, MD, Division of Infectious Disease, Kaiser Permanente Medical Center, Oakland, CA, G.Thomas Ray, MBA, Kaiser Permanente, Oakland, CA and Roger Baxter, MD, FIDSA, Kaiser Permanente Vaccine Study Center, Oakland, CA

    Disclosures:

    S. Rajagopal, None

    G. T. Ray, Pfizer: Analyst working with Grant Investigator , Research support
    Merck: Analyst working with Grant Investigator , Research support

    R. Baxter, GlaxoSmithKline: Grant Investigator , Research grant
    Merck & Co.: Grant Investigator , Research grant
    Pfizer: Grant Investigator , Research grant
    Sanofi Pasteur: Grant Investigator , Research grant
    MedImmune: Grant Investigator , Research grant
    Novartis (now GSK): Grant Investigator , Research grant
    Protein Sciences: Grant Investigator , Research grant

    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.