title: Carbapenem-resistant Enterobacteriaceae: Prevalence and Risk Factors in a Single Community-Based Hospital in Korea.
abstract: BACKGROUND
  Carbapenemase-producing Enterobacteriaceae (CPE) are Gram-negative bacteria with increasing prevalence of infection worldwide. In Korea, 25 cases of CPE isolates were reported by the Korea Centers for Disease Control and Prevention in 2011. Most CPE cases were detected mainly at tertiary referral hospitals. We analyzed the prevalence and risk factors for carbapenem-resistant Enterobacteriaceae (CRE) in a mid-sized community-based hospital in Korea.
  
  
  METHODS
  We retrospectively analyzed all consecutive episodes of Enterobacteriaceae in a mid-sized community-based hospital from January 2013 to February 2014. CRE was defined as organisms of Enterobacteriaceae showing decreased susceptibility to carbapenems. Risk factors for CRE were evaluated by a case-double control design. Carbapenemase was confirmed for CRE using a combined disc test.
  
  
  RESULTS
  During 229,710 patient-days, 2,510 Enterobacteriaceae isolates were obtained. A total of 41 (1.6%) CRE isolates were enrolled in the study period. Thirteen species (31.7%) were Enterobacter aerogenes, 8 (19.5%) Klebsiella pneumoniae, 5 (12.2%) Enterobacter cloacae, and 15 other species of Enterobacteriaceae, respectively. Among the 41 isolates, only one (2.4%) E. aerogenes isolate belonged to CPE. For evaluation of risk factors, a total of 111 patients were enrolled and this included 37 patients in the CRE group, 37 in control group I (identical species), and 37 in control group II (different species). Based on multivariate analysis, regularly visiting the outpatient clinic was a risk factor for CRE acquisition in the control group I (P = 0.003), while vascular catheter and Charlson comorbidity index score ≥ 3 were risk factors in control group II (P = 0.010 and 0.011, each). Patients with CRE were more likely to experience a reduced level of consciousness, use a vasopressor, be under intensive care, and suffer from acute kidney injury. However, CRE was not an independent predictor of mortality compared with both control groups.
  
  
  CONCLUSIONS
  In conclusion, the prevalence of CRE was higher than expected in a mid-sized community-based hospital in Korea. CRE should be considered when patients have a vascular catheter, high comorbidity score, and regular visits to the outpatient clinic. This study suggests the need for appropriate prevention efforts and constant attention to CRE infection control in a mid-sized community-based hospital.
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Hyo Jin
authors.identifier: http://orcid.org/0000-0001-9351-0779
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Jae Ki
authors.initials: JK
authors.lastname: Choi
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Sung Yeon
authors.identifier: http://orcid.org/0000-0001-5392-3405
authors.initials: SY
authors.lastname: Cho
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Si Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Park
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Su Mi
authors.identifier: http://orcid.org/0000-0002-8187-5110
authors.initials: SM
authors.lastname: Choi
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Dong Gun
authors.identifier: http://orcid.org/0000-0003-4655-0641
authors.initials: DG
authors.lastname: Lee
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Jung Hyun
authors.initials: JH
authors.lastname: Choi
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.|Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea. jhyoo@catholic.ac.kr.
authors.forename: Jin Hong
authors.identifier: http://orcid.org/0000-0003-2611-3399
authors.initials: JH
authors.lastname: Yoo
keywords: Carbapenems; Drug resistance; Enterobacteriaceae; Prevalence; Risk factors