The emergence of carbapenem resistant Klebsiella pneumoniae in Malaysia: correlation between microbiological trends with host characteristics and clinical factors

Ye-Mun Low; Polly Soo-Xi Yap; Kartini Abdul Jabar; Sasheela Ponnampalavanar; Rina Karunakaran; Rukumani Velayuthan; Chun-Wie Chong; Sazaly Abu Bakar; Mohd Yasim Md Yusof; Cindy Shuan-Ju Teh

doi:10.1186/s13756-016-0164-x

The emergence of carbapenem resistant Klebsiella pneumoniae in Malaysia: correlation between microbiological trends with host characteristics and clinical factors

Antimicrob Resist Infect Control. 2017 Jan 7:6:5. doi: 10.1186/s13756-016-0164-x. eCollection 2017.

Affiliations

¹ Department of Medical Microbiology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
² Department of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
³ Department of Life Sciences, International Medical University, Bukit Jalil, 57000 Kuala Lumpur, Malaysia.
⁴ 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.

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 resistant Klebsiella pneumoniae (K. pneumoniae) in Malaysia.

Methods: In this study, seventeen carbapenem resistant K. pneumoniae strains 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 resistant K. pneumoniae and in-hospital mortality.

Results: The predominant carbapenemase was bla_OXA-48, detected in 12 strains (70.59%). Other carbapenemases detected in this study were bla_KPC-2, bla_IMP-8, bla_NMC-A and bla_NDM-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.

Conclusion: The diverse genetic mechanisms harbored by these carbapenem resistant K. pneumoniae facilitates 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.

Keywords: Carbapenem resistant K. pneumoniae; Enterobacteriaceae; KPC-2; OXA-48; ST101.