JAC Advance Access originally published online on March 10, 2006
Journal of Antimicrobial Chemotherapy 2006 57(5):1014-1016; doi:10.1093/jac/dkl062
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Correspondence |
CTX-M-15, OXA-30 and TEM-1-producing Escherichia coli in two Portuguese regions
1 Antibiotic Resistance Unit, Centre of Bacteriology, National Institute of Health Dr Ricardo Jorge, Avenida Padre Cruz, 1649-016 Lisboa, Portugal; 2 Laboratory of Microbiology, Centro Hospitalar Vila Real-Peso da Régua S.A., Portugal; 3 Laboratory of Microbiology, Hospital Garcia de Orta S.A., Portugal
* Corresponding author. Tel/Fax: +351-217519246; E-mail: manuela.canica{at}insa.min-saude.pt
Keywords: extended-spectrum cephalosporins , antimicrobial resistance , ß-lactamases , Enterobacteriaceae , Portugal
Sir,
Currently, CTX-M-type enzymes are the most common group of extended-spectrum ß-lactamases (ESBLs) not belonging to the TEM and SHV families.1
Here, we report the phenotypic and molecular characterization of two Portuguese strains of Escherichia coli harbouring CTX-M-15. Both strains were isolated in 2004. One strain (INSRA5753), isolated at Hospital Garcia de Orta in Lisbon, was from the urine of a 78-year-old woman who was living in a residential care home, using a catheter. The other strain (INSRA5754) was isolated from the blood of a 90-year-old woman 1 day after hospitalization in Vila Real. These two hospitals are about 400 km apart. The strains were detected as ESBL-producers in the hospitals, using the VITEK 1 system and ATB G-5, respectively.
In the Antibiotic Resistance Unit, at the National Institute of Health in Lisbon, ß-lactamase production was confirmed using the Etest ESBL screen method. Using PCR, fragments indicating the presence of the blaTEM gene, the blaOXA gene, the blaCTX gene and the ubiquitous ampC gene were amplified from both strains.2–4 The amplification products from blaTEM, blaOXA and blaCTX genes from both strains were then purified and sequenced. For sequencing of the blaCTX-M-15 gene, we used primers specific for the consensus of CTX-M group I: CTX-M-15F, 5'-AGAATAAGGAATCCCATGGTT-3' and CTX-M-15R, 5'-ACCGTCGGTGACGATTTTAG-3'. Sequencing confirmed three resistance genes in both strains, namely blaTEM-1B, blaOXA-30 and blaCTX-M-15. Sequence analysis using CTX-M-15 primers and ISEcp1, IS26 or IS903r primers5 indicated the presence of an ISEcp1-like element in both strains although neither had IS903, thus differing from the mobile elements of the blaCTX-M-15 gene detected previously in Klebsiella pneumoniae.6 The IS26 element was also not present in our strains. These findings suggest that CTX-M-15 enzymes in these two species in Portugal might have emerged in multiple places by plasmid acquisition of blaCTX-M-15 genes, with different elements implicated in the dissemination of these ß-lactamase genes.6 This was corroborated by the PFGE analysis, which showed different clonal origins for each isolate (data not shown).
The transconjugant C600-URA5753 was a CTX-M-15-positive-transconjugant from E. coli INSRA5753 derived using C600 as the recipient. The transconjugant C600-URA5754 co-expressed CTX-M-15, OXA-30 and TEM-1 enzymes; indeed, none of these enzymes was transferable alone from E. coli INSRA5754 strain to E. coli C600 (Table 1), suggesting that the blaCTX-M-15 gene was carried in only one transferable plasmid with blaTEM-1B and blaOXA-30. MICs of various ß-lactams, alone or in combination with ß-lactamase inhibitors (Table 1), were determined using an agar dilution method,2 and MICs of other antimicrobial agents were determined using a broth microdilution method. The clinical isolates and the transconjugants showed a higher level of resistance to cefotaxime, ceftriaxone and aztreonam than to ceftazidime, which is characteristic of CTX-M producers. Isoelectric focusing revealed that both the clinical strain and transconjugant C600-URA5754 produced ß-lactamases with pIs of 5.4 (TEM-1), 7.5 (OXA-30) and 8.9 (CTX-M-15). Transconjugant C600-URA5753 produced a ß-lactamase with a pI of 8.9.
|
To our knowledge the combination of CTX-M-15, TEM-1 and OXA-30 ß-lactamases, here reported, was described previously only in strains from Senegal.7 However, the combination of CTX-M-15 and OXA-1 (similar to OXA-30) has been described in the UK, Canada and India.1,8 The spread of resistance to extended-spectrum cephalosporins, their extensive use, and the coexistence of strains co-expressing the same TEM, OXA and CTX-M enzymes in distant regions of Portugal may impede the use of ß-lactams in other regions of the country. These cases involving hospital and community environments are consistent with dissemination either from or to the community, which is of high concern.
Transparency declarations
None to declare.
Acknowledgements
Nuno Mendonça was supported by the Portuguese ‘NIH Scientific Research Ricardo-Jorge’ grant. This work was supported financially by the POCTI/2001/ESP/43037 (38% FEDER) grant from Fundação para a Ciência e a Tecnologia, Portugal.
References
1.
Livermore D, Hawkey P. CTX-M: changing the face of ESBLs in the UK. J Antimicrob Chemother 2005; 56: 451–4.
2.
Féria C, Ferreira E, Correia JD et al. Patterns and mechanisms of resistance to ß-lactams and ß-lactamase inhibitors in uropathogenic Escherichia coli isolated from dogs in Portugal. J Antimicrob Chemother 2002; 49: 77–85.
3.
Edelstein M, Pimkin M, Palagin I et al. Prevalence and molecular epidemiology of CTX-M extended-spectrum ß-lactamase-producing Escherichia coli and Klebsiella pneumoniae in Russian hospitals. Antimicrob Agents Chemother 2003; 47: 3724–32.
4. Casin I, Breuil J, Brisabois A et al. Multidrug-resistant human and animal Salmonella typhimurium isolates in France belong predominantly to a DT104 clone with the chromosome- and integron-encoded ß-lactamase PSE-1. J Infect Dis 1999; 179: 1173–82.[CrossRef][Web of Science][Medline]
5.
Eckert C, Gautier V, Saladin-Allard M et al. Dissemination of CTX-M-type ß-lactamases among clinical isolates of Enterobacteriaceae in Paris, France. Antimicrob Agents Chemother 2004; 48: 1249–55.
6.
Conceição T, Brizio A, Duarte A et al. First description of CTX-M-15-producing Klebsiella pneumoniae in Portugal. Antimicrob Agents Chemother 2005; 49: 477–8.
7. Weill F-X, Perrier-Gros-Claude J-D, Demartin M et al. Characterization of extended-spectrum-ß-lactamase (CTX-M-15)-producing strains of Salmonella enterica isolated in France and Senegal. FEMS Microbiol Lett 2004; 238: 353–8.[Medline]
8.
Boyd D, Tyler S, Christianson S et al. Complete nucleotide sequence of a 92-kilobase plasmid harboring the CTX-M-15 extended-spectrum ß-lactamase involved in an outbreak in long-term-care facilities in Toronto, Canada. Antimicrob Agents Chemother 2004; 48: 3758–64.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  N. Mendonca, J. Leitao, V. Manageiro, E. Ferreira, the Antimicrobial Resistance Surveillance Program, and M. Canica Spread of Extended-Spectrum {beta}-Lactamase CTX-M-Producing Escherichia coli Clinical Isolates in Community and Nosocomial Environments in Portugal Antimicrob. Agents Chemother., June 1, 2007; 51(6): 1946 - 1955. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Bogaerts, M. Galimand, C. Bauraing, A. Deplano, R. Vanhoof, R. De Mendonca, H. Rodriguez-Villalobos, M. Struelens, and Y. Glupczynski Emergence of ArmA and RmtB aminoglycoside resistance 16S rRNA methylases in Belgium J. Antimicrob. Chemother., March 1, 2007; 59(3): 459 - 464. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. M. Livermore, R. Canton, M. Gniadkowski, P. Nordmann, G. M. Rossolini, G. Arlet, J. Ayala, T. M. Coque, I. Kern-Zdanowicz, F. Luzzaro, et al. CTX-M: changing the face of ESBLs in Europe J. Antimicrob. Chemother., February 1, 2007; 59(2): 165 - 174. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Costa, P. Poeta, Y. Saenz, L. Vinue, B. Rojo-Bezares, A. Jouini, M. Zarazaga, J. Rodrigues, and C. Torres Detection of Escherichia coli harbouring extended-spectrum {beta}-lactamases of the CTX-M, TEM and SHV classes in faecal samples of wild animals in Portugal J. Antimicrob. Chemother., December 1, 2006; 58(6): 1311 - 1312. [Full Text] [PDF]
|
|
|
|
 |
|
 N. Ramdani-Bouguessa, N. Mendonca, J. Leitao, E. Ferreira, M. Tazir, and M. Canica CTX-M-3 and CTX-M-15 Extended-Spectrum {beta}-Lactamases in Isolates of Escherichia coli from a Hospital in Algiers, Algeria J. Clin. Microbiol., December 1, 2006; 44(12): 4584 - 4586. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Machado, T. M. Coque, R. Canton, F. Baquero, J. C. Sousa, L. Peixe, and The Portuguese Resistance Study Group Dissemination in Portugal of CTX-M-15-, OXA-1-, and TEM-1-Producing Enterobacteriaceae Strains Containing the aac(6')-Ib-cr Gene, Which Encodes an Aminoglycoside- and Fluoroquinolone-Modifying Enzyme Antimicrob. Agents Chemother., September 1, 2006; 50(9): 3220 - 3221. [Full Text] [PDF]
|
|
|
|
|
|
D. A. Boyd and M. R. Mulvey OXA-1 is OXA-30 is OXA-1 J. Antimicrob. Chemother., July 1, 2006; 58(1): 224 - 225. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||