Vol 50, No 1 (2012)
Original paper
Submitted: 2012-04-24
Accepted: 2012-04-24
Susceptibility, phenotypes of resistance, and extended-spectrum β-lactamases in Acinetobacter baumannii strains
Pawel Sacha, Piotr Wieczorek, Dominika Ojdana, Slawomir Czaban, Wioletta Kłosowska, Anna Jurczak, Elzbieta Tryniszewska
DOI: 10.5603/FHC.2012.0006
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Folia Histochem Cytobiol 2012;50(1):46-51.
Vol 50, No 1 (2012)
ORIGINAL PAPERS
Submitted: 2012-04-24
Accepted: 2012-04-24
Abstract
Acinetobacter baumannii plays an increasing role in the pathogenesis of infections in humans. The bacilli are frequently isolated from patients treated in intensive care units. A growing resistance to antibiotics is leading to the emergence of strains that are multidrug-resistant and resistant to all available agents. The objective of this study was to assess susceptibility to antibiotics and to determine the presence and current level of the extended-spectrum β-lactamases (ESBLs) and attempt to isolate the Acinetobacter baumannii strain carrying the blaPER gene. A total of 51 strains of A. baumannii identified by phenotypic features were examined. That the strains belonged to the species was confirmed by the presence of the blaOXA-51-like; gene. A broth microdilution method was used for antibacterial susceptibility testing. The occurrence of ESBLs was determined using phenotypic double-disk synergy tests. The PCR technique was used to confirm the presence of the blaPER-1; gene encoding ESBL. The most active antibiotics were meropenem, cefepime and ampicillin/sulbactam, with susceptibility shown by 76.5%, 60.8% and 56.9% of the strains, respectively. The strains exhibited the highest resistance (> 75%) to piperacillin, tetracycline, ciprofloxacin and cefotaxime. Phenotypic tests revealed ESBL mechanism of resistance in approximately 20% of Acinetobacter baumannii isolates. However, the PCR technique did not confirm the presence of the blaPER-1; gene in any of the Acinetobacter baumannii strains examined in our hospital. Acinetobacter baumannii strains demonstrate considerable resistance to many groups of antibiotics. Our findings indicate the involvement of enzymes belonging to families other than PER β-lactamase in resistance to β-lactams in A. baumannii.
Abstract
Acinetobacter baumannii plays an increasing role in the pathogenesis of infections in humans. The bacilli are frequently isolated from patients treated in intensive care units. A growing resistance to antibiotics is leading to the emergence of strains that are multidrug-resistant and resistant to all available agents. The objective of this study was to assess susceptibility to antibiotics and to determine the presence and current level of the extended-spectrum β-lactamases (ESBLs) and attempt to isolate the Acinetobacter baumannii strain carrying the blaPER gene. A total of 51 strains of A. baumannii identified by phenotypic features were examined. That the strains belonged to the species was confirmed by the presence of the blaOXA-51-like; gene. A broth microdilution method was used for antibacterial susceptibility testing. The occurrence of ESBLs was determined using phenotypic double-disk synergy tests. The PCR technique was used to confirm the presence of the blaPER-1; gene encoding ESBL. The most active antibiotics were meropenem, cefepime and ampicillin/sulbactam, with susceptibility shown by 76.5%, 60.8% and 56.9% of the strains, respectively. The strains exhibited the highest resistance (> 75%) to piperacillin, tetracycline, ciprofloxacin and cefotaxime. Phenotypic tests revealed ESBL mechanism of resistance in approximately 20% of Acinetobacter baumannii isolates. However, the PCR technique did not confirm the presence of the blaPER-1; gene in any of the Acinetobacter baumannii strains examined in our hospital. Acinetobacter baumannii strains demonstrate considerable resistance to many groups of antibiotics. Our findings indicate the involvement of enzymes belonging to families other than PER β-lactamase in resistance to β-lactams in A. baumannii.
Keywords
Acinetobacter baumannii; susceptibility to antibiotics; extended-spectrum beta-lactamase
Title
Susceptibility, phenotypes of resistance, and extended-spectrum β-lactamases in Acinetobacter baumannii strains
Journal
Folia Histochemica et Cytobiologica
Issue
Vol 50, No 1 (2012)
Article type
Original paper
Pages
46-51
Page views
2170
Article views/downloads
2339
DOI
10.5603/FHC.2012.0006
Bibliographic record
Folia Histochem Cytobiol 2012;50(1):46-51.
Keywords
Acinetobacter baumannii
susceptibility to antibiotics
extended-spectrum beta-lactamase
Authors
Pawel Sacha
Piotr Wieczorek
Dominika Ojdana
Slawomir Czaban
Wioletta Kłosowska
Anna Jurczak
Elzbieta Tryniszewska