219. Comparison of Trends and Characteristics of Extended-Spectrum Beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in Bloodstream Isolates
Session: Poster Abstract Session: Antimicrobial Resistance: Clinical Studies
Friday, October 21, 2011
Room: Poster Hall B1


The rate of ESBL-producing stains among Escherichia coli and Klebsiella pneumoniae has been reported to increase in many countries. The purpose of this study was to compare the difference of epidemiologic characteristics of ESBL-producing E. coli and K. pneumoniae.


The study was performed in Gachon University Gil Hospital, 1200-bed, tertiary teaching hospital in western Korea. We retrospectively collected the blood culture data of ESBL-producing E. coli and K. pneumoniae between 2003 and 2010, confirmed by double disk synergy test for ESBL detection. The strains were classified as "community inflow (CI)", if the first positive blood culture was obtained within 2 calendar days of admission or at outpatient department. And those from patients who had been hospitalized for more than 48 hours were defined as "hospital-acquired (HA)". Trend for linearity was tested using EpiInfo version 6 (CDC, USA).


A total of 2969 first blood culture isolate were identified as E. coli (n = 2160) and K. pneumoniae (n = 809), and ESBL producer was 8.56% (n = 254; E. coli, 193; K. pneumoniae, 61). Overall rate of two ESBL-producing pathogens were significantly increasing (p < 0.001), mainly due to E. coli (p < 0.001, K. pneumoniae; p = 0.13) during 8 years. Department of emergency medicine (EM) was more common source of CI ESBL producers and department of gastrointestinal medicine (GI), and hemato-onlocogy (HMO) were more related with HA ESBL producers. Further analysis of ESBL E. coli reveals that CI and HA ESBL E. coli uniformly increasing (1 to 18, p < 0.001 and 0 to 36, p < 0.001). Age and sex were not linked with ESBL producing trends.


During 8 years, ESBL-producing E. coli was substantially increased, mainly due to CI pathogens. However the incidence of ESBL-producing K. pneumoniae was remained stable regardless of acquisition site. Department of EM, GI, and HMO were linked with the probability of ESBL-producing E. coli and K. pneumoniae infections.

Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

Jin Sun Park, MD, Byung Hoon Kim, MD, Jin Yong Kim, MD and Yong Kyun Cho, MD, Gachon University Gil Hospital, Incheon, South Korea


J. S. Park, None

B. H. Kim, None

J. Y. Kim, None

Y. K. Cho, None

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