1794. An Outbreak with Colistin- and Carbapenem-Resistant Klebsiella pneumoniae in an Intensive Care Unit
Session: Poster Abstract Session: Resistant Gram-Negative Infections: CRE Epidemiology
Saturday, October 10, 2015
Room: Poster Hall
Posters
  • US_ID_week_2015_poster_CRE_FINAL.pdf (531.6 kB)
  • Background: Colistin is commonly used for the treatment of infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). Unfortunately, colistin resistance emerged in CRKP. Optimal treatment of infections with colistin-resistant CRKP (ColR_CRKP) has not been defined yet.

    Methods: We report a large outbreak with ColR_CRKP in a 16-bed surgical intensive care unit of a university hospital from January to July, 2014. Control of this outbreak was prolonged due to delay in total closure of the unit. We retrospectively evaluated characteristics and outcomes of adult patients infected or colonized with ColR_CRKP. Methods and breakpoints described by The European Committee on Antimicrobial Susceptibility Testing were used for determination of antibiotic resistance. Clonality was determined using repetitive extragenic palindromic PCR.

    Results: During the outbreak, 17 patients were infected with ColR_CRKP while 16 patients remained colonized. Two separate clones were identified. Among infections, there were 10 bacteremias (8 central venous catheter-associated), 7 ventilator-associated pneumonias, 4 urinary catheter-associated urinary tract infections and 3 surgical site infections. Some patients had multiple infected sites. The 14-day, 28-day and in-hospital fatality rates were 35.3%, 52.9% and 82.4% among infected; these rates were similar in colonized patients. Infected patients had significantly lower colistin minimal inhibitory concentrations (median 4 [range 3-16] mg/L) than colonized patients (16 [8-16] mg/L, p=0.001). Using one in vitro active agent in addition to colistin and/or meropenem was considered adequate treatment. Most ColR_CRKP isolates (94%) were susceptible to trimethoprim/ sulfamethoxazole (TMP-SMX). Only 7 of 17 patients received adequate treatment, but this was not associated with survival. Among factors associated with fatality, only carbapenem use prior to infection diagnosis was significantly associated with fatal outcome (8/9 in fatal vs. 2/8 in nonfatal, p=0.029).

    Conclusion: ColR_CRKP appears to have about 50% infection-to-colonization ratio with high fatality rates. Most strains are susceptible to TMP-SMX. Further studies are needed to determine the effectiveness of TMP-SMX alone or in combination for the treatment of ColR_CRKP infections.

    Uluhan Sili, MD, PhD1, Aysun Tekin, MD1, Husniye Karadag, RN1, Gulsen Altinkanat, PhD2, Fethi Gul, MD3, Beliz Bilgili, MD3, Mustafa Kemal Arslantas, MD3, Pinar Ay, MD, PhD4, Guner Soyletir, MD2, Ismail Cinel, MD, PhD3 and Volkan Korten, MD1, (1)Infectious Diseases and Clinical Microbiology, Marmara University, School of Medicine, Pendik Training and Research Hospital, Istanbul, Turkey, (2)Microbiology, Marmara University, School of Medicine, Pendik Training and Research Hospital, Istanbul, Turkey, (3)Anesthesiology and Reanimation, Marmara University, School of Medicine, Pendik Training and Research Hospital, Istanbul, Turkey, (4)Public Health, Marmara University, School of Medicine, Pendik Training and Research Hospital, Istanbul, Turkey

    Disclosures:

    U. Sili, None

    A. Tekin, None

    H. Karadag, None

    G. Altinkanat, None

    F. Gul, None

    B. Bilgili, None

    M. K. Arslantas, None

    P. Ay, None

    G. Soyletir, None

    I. Cinel, None

    V. Korten, None

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 7th with the exception of research findings presented at the IDWeek press conferences.