Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2011 Jun;3(2):68-74.

Isolation and genetic characterization of metallo-β-lactamase and carbapenamase producing strains of Acinetobacter baumannii from patients at Tehran hospitals

Affiliations

Isolation and genetic characterization of metallo-β-lactamase and carbapenamase producing strains of Acinetobacter baumannii from patients at Tehran hospitals

F Shahcheraghi et al. Iran J Microbiol. 2011 Jun.

Abstract

Background and objective: Carbapenems are therapeutic choice against infections caused by gram-negative bacilli including strains of Acinetobacter baumannii. Resistance to these antibiotics is mediated by efflux pumps, porins, PBPs and ß-lactamases. The aim of this study was to determine the possibility of existence of MBLs, OXAs and GES-1 betalactamase genes among clinical isolates of Acinetobacter collected from Tehran hospitals.

Material and methods: Two hundred and three Acinetobacter isolates were collected from patient at Tehran hospitals. The isolates were identified using biochemical tests. The susceptibility to different antibiotics was evaluated by disk diffusion method and MICs of imipenem were determined using Micro broth dilution method (CLSI). PCR was performed for detection of bla(VIM-2), bla(SPM-1), bla(IMP-2), bla(GES-1), bla(OXA-51), bla(OXA-23) betalactamase genes. Clonal relatedness was estimated by PFGE with the restriction enzyme SmaI.

Results and conclusion: Of 100 isolates of imipenem resistant Acinetobacter spp. collected from Tehran hospitals in 2009 and 2010, 6 isolates produced metallo-beta-lactamases and 94 isolates produced OXA-type carbapenemase. The bla(SPM-1), bla(GES-1), bla(OXA-51), bla(OXA-23) genes were detected by PCR among 6, 2, 94 and 84 isolates of A. baumannii, respectively. The MICs of isolates to imipenem were 8-128 µg/mL. PFGE analysis of 29 bla(OXA-51) and bla(OXA-23)-positive A. baumannii isolates gave 6 different patterns. This is the first report of SPM-1 and GES-1 beta-lactamase producing A. baumannii. Production of the OXA-23, OXA-51, GES-1 and SPM-1 enzyme presents an emerging threat of carbapenem resistance among A. baumannii in Iran.

Keywords: Acinetobacter; OXA-type; betalactamase; metallo beta lactamase.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Dendrogram of the six (A–F) pulsed field gel electrophoresis profile of Smal-digested genomic DNAfrom 26 blaOXA-23 positive A. baumannii isolates were from hospital A to E.

References

    1. Sinha M, Srinivasa H, Macaden R. Antibiotic resistance. profile and extended spectrum beta-lactamase (ESBL) production in Acinetobacter species. Ind J Med Res. 2007;126:63–67. - PubMed
    1. Sinha M, Srinivasa H. Mechanism of Resistance to. Crabapenem-resistant Acinetobacter Isolates from Clinical Sample. Ind. J Med Microbiol. 2007;25:121–5. - PubMed
    1. Walsh TR, Toleman MA, Poirel L, Nordmann P. Metallo-β-Lactamases: the Quiet before the Storm? J. Clin. Microbiol. 2002;18:3798–3801. - PMC - PubMed
    1. Feizabadi MM, Fathollahzadeh B, Taheri-Kalani M, Rasoolinejad M, Sadeghifard N, Aligholi M. Antimicrobial susceptibility patterns and distribiution of bla OXA genes among Acinetobacter spp. Isolated from patients at Tehran hospital. Jpn. J Infect Dis. 2008;61:274–278. - PubMed
    1. Jeong SH, Bae IK, Park KO, An YJ, Sohn SG, Sung KH, et al. Outbreaks of imipenem-resistant Acinetobacter baumannii produc-ing carbapenemes in Korea. J Microbiol. 2006;44:423–431. - PubMed

LinkOut - more resources