title: The emergence of carbapenem resistantKlebsiella pneumoniaein Malaysia: correlation between microbiological trends with host characteristics and clinical factors.
abstract: BACKGROUND
  Carbapenem resistant Enterobacteriaceae is a growing concern worldwide including Malaysia. The emergence of this pathogen is worrying because carbapenem is one of the 'last-line' antibiotics. The main objective of this study was to determine the prevalence of genetic mechanisms and clinical risk factors of carbapenem resistantKlebsiella pneumoniae (K. pneumoniae)in Malaysia.
  
  
  METHODS
  In this study, seventeen carbapenem resistantK. pneumoniaestrains isolated from a tertiary teaching hospital in 2013 were studied. Minimal inhibitory concentration (MIC) of the bacterial strains was determined and genes associated with carbapenemases and extended-spectrum-beta-lactamases (ESBLs) were sequenced and compared with the closest representatives published in public domains. All strains were also sub-typed using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Statistical analyses were performed to determine the correlation between risk factors for acquiring carbapenem resistantK. pneumoniaeand in-hospital mortality.
  
  
  RESULTS
  The predominant carbapenemase wasblaOXA-48, detected in 12 strains (70.59%). Other carbapenemases detected in this study wereblaKPC-2,blaIMP-8,blaNMC-AandblaNDM-1. Nine different pulsotypes were identified and nine strains which were affiliated with ST101, the predominant sequence type had similar PFGE patterns (similarity index of 85%). Based on univariate statistical analysis, resistance to imipenem and usage of mechanical ventilation showed a statistically significant effect separately to in-hospital mortality.
  
  
  CONCLUSIONS
  The diverse genetic mechanisms harbored by these carbapenem resistantK. pneumoniaefacilitates its spread and complicates its detection. Thus, correlation between microbiological trends with host characteristics and clinical factors will provide a better insight of rational treatment strategies and pathogen control.
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Ye-Mun
authors.initials: YM
authors.lastname: Low
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Polly Soo-Xi
authors.initials: PS
authors.lastname: Yap
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Kartini
authors.initials: K
authors.lastname: Abdul Jabar
authors.affiliation: Department of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Sasheela
authors.initials: S
authors.lastname: Ponnampalavanar
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Rina
authors.initials: R
authors.lastname: Karunakaran
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Rukumani
authors.initials: R
authors.lastname: Velayuthan
authors.affiliation: Department of Life Sciences, International Medical University, Bukit Jalil, 57000 Kuala Lumpur, Malaysia.
authors.forename: Chun-Wie
authors.initials: CW
authors.lastname: Chong
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia ; The Tropical Infectious Diseases Research & Education Centre (TIDREC), University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Sazaly
authors.initials: S
authors.lastname: Abu Bakar
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Mohd Yasim
authors.initials: MY
authors.lastname: Md Yusof
authors.affiliation: Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Cindy Shuan-Ju
authors.initials: CS
authors.lastname: Teh
keywords: Carbapenem resistant K. pneumoniae; Enterobacteriaceae; KPC-2; OXA-48; ST101