Metallolactamases among Enterobacteriaceae from routine samples in an Italian tertiary care hospital and long-term care facilities during 2009

Abstract number: P1280

Aschbacher R., Pagani L., Spoladore G., Innocenti P., Moroder L., Meyer R., Pagani E., Livermore D., Larcher C.

Objectives: Metallo-b-lactamase (MBLs) producing Enterobacteriaceae have been isolated since 2005 in a 850-bed tertiary care hospital and associated long-term care facilities, serving an area of 200,000 inhabitants, in Bolzano, Italy. All routine isolates in 2009 were screened for MBLs and case details were reviewed for source patients.

Methods: Basic screening of Enterobacteriaceae with the Vitek 2 automatic system using cards that included an ESBL-confirmation test. Carbapenemase and MBL activity were sought with Hodge-cloverleaf and EDTA-synergy tests, respectively; VIM- genes were sought by PCR. Clinical data were collected retrospectively.

Results: The prevalence of MBL producing Enterobacteriaceae from in- and out-patient samples during the first 9 months in 2009 was 0.67% (28/4200), almost exactly the same as in 2008 (0.65%; 36/5,500). All the producer strains from both years had VIM enzymes. Prevalence rates in 2009 varied from 0.4% (13/3,000) for E. coli, 0.8% (1/126) for E. cloacae, 1.6% (6/372) for K. pneumoniae, 2.2% (1/46) for C. freundii, 2.3% (1/44) for E. aerogenes, 2.3% (3/129) for K. oxytoca up to 3.1% (2/64) for M. morganii, together with 1/1 for C. amalonaticus. These 28 MBL-producers were from 26 patients (one patient had MBL-positive E. coli, K. pneumoniae and K. oxytoca) in 8 hospital departments (14 isolates), 4 long-term care facilities (7 isolates) or outpatients (7 isolates); risk factors in the latter group remain unspecified. Seventeen were from urine samples (8 E. coli, 4 K. pneumoniae, 2 M. morganii, 1 E. cloacae, 1 E. aerogenes and 1 C. amalonaticus); two were from blood (1 K. pneumoniae and 1 C. freundii), 7 were from respiratory specimens (4 E. coli, 2 K. pneumoniae and 3 K. oxytoca); the remaining 2 were from peritoneal fluid (E. coli) and an ulcer (K. pneumoniae). Altogether 88 MBL-producing Enterobacteriaceae belonging to 10 species have been isolated since 2005.

Conclusion: Isolation of VIM MBL-producing Enterobacteriaceae from eight hospital departments and four long-term care facilities or nursing homes confirms the endemic persistance of this mode of resistance and its encoding elements in the Bolzano health care district.

Session Details

Date: 10/04/2010
Time: 00:00-00:00
Session name: Abstracts 20th European Congress of Clinical Microbiology and Infectious Diseases
Location: Vienna, Austria, 10 - 13 April 2010
Presentation type:
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