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Year : 2013  |  Volume : 31  |  Issue : 1  |  Page : 53--59

Detection of plasmid-mediated AmpC β-lactamase in Escherichia coli and Klebsiella pneumoniae

NO Yilmaz1, N Agus1, E Bozcal2, O Oner2, A Uzel2 
1 Department of Microbiology Laboratory, Tepecik Educational and Research Hospital , Ege University, Izmir, Turkey
2 Department of Biology, Basic and Industrial Microbiology Section, Izmir, Turkey

Correspondence Address:
N O Yilmaz
Department of Microbiology Laboratory, Tepecik Educational and Research Hospital , Ege University, Izmir
Turkey

Background: Detecting plasmid-mediated AmpC (pAmpC) β-lactamase-producing organism is important for optimal infection control and providing accurate and effective treatment option for physicians. Objectives: The aim of this study was to investigate the prevalence of pAmpC β-lactamase and compare the results of boronic acid (BA) disk test with other phenotypic tests detecting AmpC positive isolates. Materials and Methods: A total of 273 clinical isolates of Klebsiella pneumoniae (n: 82) and Escherichia coli (n: 191) were analysed. The presence of pAmpC β-lactamase was determined by BA disk test, cefoxitin (FOX) screening test, modified three dimensional test (M3DT), and multiplex polymerase chain reaction (PCR). Pulsed-field gel electrophoresis was performed to evaluate the genetic similarities between isolates. To detect extended spectrum β-lactamases (ESBL) in the presence of AmpC β-lactamase, ESBL confirmation test was carried out with and without BA solution. Results: Of the 273 strains tested, 127 strains were found FOX resistant, 114 were positive by M3DT, 108 were positive in BA disk test, and the multiplex PCR detected 24 pAmpC β-lactamase-positive isolate. The prevalence of AmpC-producing strains was 10.9% in E. coli and 3.6% in K. pneumoniae in the tested population by PCR. CIT and MOX group genes were predominant type in these strains. Conclusion: These results emphasize that clinical laboratories should consider testing the presence of pAmpC enzymes particularly in FOX-resistant isolates, and BA disk test will improve detection of this emerging resistance phenotype.

How to cite this article:
Yilmaz N O, Agus N, Bozcal E, Oner O, Uzel A. Detection of plasmid-mediated AmpC β-lactamase in Escherichia coli and Klebsiella pneumoniae.Indian J Med Microbiol 2013;31:53-59

How to cite this URL:
Yilmaz N O, Agus N, Bozcal E, Oner O, Uzel A. Detection of plasmid-mediated AmpC β-lactamase in Escherichia coli and Klebsiella pneumoniae. Indian J Med Microbiol [serial online] 2013 [cited 2020 Feb 27 ];31:53-59
Available from: http://www.ijmm.org/article.asp?issn=0255-0857;year=2013;volume=31;issue=1;spage=53;epage=59;aulast=Yilmaz;type=0