Multi-drug resistance profiles and the genetic features of Acinetobacter baumannii isolates from Bolivia

Authors

  • Bruno Silvester Lopes The University of Edinburgh, Edinburgh, United Kingdom
  • Lucia Gallego Facultad de Medicina y Odontología, Universidad del País Vasco, Campus de Bizkaia, Leioa, Spain
  • Sebastian Giles Becket Amyes The University of Edinburgh, Edinburgh, United Kingdom

DOI:

https://doi.org/10.3855/jidc.2711

Keywords:

Acinetobacter baumannii, insertion sequences, beta-lactamases, carbapenems, gene, environment

Abstract

Introduction: Acinetobacter baumannii is opportunistic in debilitated hospitalised patients. Because information from some South American countries was previously lacking, this study examined the emergence of multi-resistant A. baumannii in three hospitals in Cochabamba, Bolivia, from 2008 to 2009.

Methodology: Multiplex PCR was used to identify the main resistance genes in 15 multi-resistant A. baumannii isolates. RT-PCR was used to measure gene expression. The genetic environment of these genes was also analysed by PCR amplification and sequencing. Minimum inhibitory concentrations were determined for key antibiotics and some were determined in the presence of an efflux pump inhibitor, 1-(1-napthylmethyl) piperazine.

Results: Fourteen strains were found to be multi-resistant. Each strain was found to have the blaOXA-58 gene with the ISAba3-like element upstream, responsible for over-expression of the latter and subsequent carbapenem resistance. Similarly, ISAba1, upstream of the blaADC gene caused over-expression of the latter and cephalosporin resistance; mutations in the gyrA(Ser83 to Leu) and parC (Ser-80 to Phe) genes were commensurate with fluoroquinolone resistance. In addition, the adeA, adeB efflux genes were over-expressed. All 15 isolates were positive for at least two aminoglycoside resistance genes.

Conclusion: This is one of the first reports analyzing the multi-drug resistance profile of A. baumannii strains isolated in Bolivia and shows that the over-expression of theblaOXA-58, blaADC and efflux genes together with aminoglycoside modifying enzymes and mutations in DNA topoisomerases are responsible for the multi-resistance of the bacteria and the subsequent difficulty in treating infections caused by them.

Author Biographies

Bruno Silvester Lopes, The University of Edinburgh, Edinburgh, United Kingdom

Medical Microbiology

Post-doctoral research fellow

Lucia Gallego, Facultad de Medicina y Odontología, Universidad del País Vasco, Campus de Bizkaia, Leioa, Spain

Departmento Inmunología, Microbiología y Parasitología,

Professor

Sebastian Giles Becket Amyes, The University of Edinburgh, Edinburgh, United Kingdom

Medical Microbiology

Professor

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Published

2013-04-17

How to Cite

1.
Lopes BS, Gallego L, Amyes SGB (2013) Multi-drug resistance profiles and the genetic features of Acinetobacter baumannii isolates from Bolivia. J Infect Dev Ctries 7:323–328. doi: 10.3855/jidc.2711

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Section

Original Articles