386. Effect of Strict Contact Precaution to Reduce Spread of Carbapenem-Resistant Enterobacteriaceae
Session: Poster Abstract Session: Gram Negative Infection - Epidemiology and Prevention
Friday, October 21, 2011
Room: Poster Hall B1
Background: 

As carbapenem resistance among Enterobacteriaceae increases, infection control measures based on understanding of resistance mechanisms became more important. Carbapenem-resistant Enterobacteriaceae (CRE) increased excessively during 2009 in our institution (a tertiary hospital, South Korea). We tried to reduce spread of CRE by enhancing infection control measures. We also investigated resistance mechanisms among carbapenem-resistant (CR) Escherichia coli (ECO) and Klebsiella pneumoniae (KPN).

Methods: 

Since the 2nd trimester 2010, strict individual contact precautions including hand hygiene and cohort isolation were performed according to WHO infection control guidelines. Performances of hand hygiene were monitored by active surveillance and results were monthly fed back to medical personnel. From Jan 2008 to Dec 2010, clinical ECO and KPN isolates were reviewed. CRE were defined by the revised CLSI breakpoints. Imipenem and meropenem minimal inhibitory concentrations were confirmed by E-test. To characterize CRE isolates, phenotypic screening assays and PCR amplification of known beta-lactamase and carbapenemase genes were performed.

Results: 

From 5790 Enterobacteriaceae (3511 ECO, 2279 KPN) 44 (0.76%) were determined as CRE (3 ECO, 41 KPN). The proportion of CRE was 0.28% (5/1727) in 2008, which rose to 0.88% (17/1941) in 2009 and further to 1.69% (11/652) in the 1st trimester 2010. After strict infection control measures were adopted in the 2nd trimester 2010, CRE proportion started to decrease in the 2nd trimester (1.20%, 9/748) and decreased to 0.28% (2/722) in the 3rd trimester 2010 (p=0.395).

Of 17 isolates (3 ECO, 14 KPN) available, 13 (76.5%) had an AmpC beta-lactamase gene, and 17 (100%) had more than one extended-spectrum beta-lactamase (ESBL) gene. Carbapenemases were not identified by either phenotypic screening or PCR.

Conclusion: 

Strict contact precautions and cohort isolation were effective to prevent further spread of CRE. AmpC beta-lactamase and ESBL production rather than carbapenemase production seem to play an important role in carbapenem resistance among Enterobacteriaceae in our institution.


Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

Nak-Hyun Kim, MD, Jeong-Hwan Hwang, MD, Jinyong Park, MD, Kyoung-Ho Song, MD, Pyoeng Gyun Choe, MD, Wan Beom Park, MD, PhD, Eu Suk Kim, MD, PhD, Hong Bin Kim, MD, PhD, Nam-Joong Kim, MD and Myoung-don Oh, MD, PhD, Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea

Disclosures:

N. H. Kim, None

J. H. Hwang, None

J. Park, None

K. H. Song, None

P. G. Choe, None

W. B. Park, None

E. S. Kim, None

H. B. Kim, None

N. J. Kim, None

M. D. Oh, None

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