Genetic Determinants of Antibacterial Resistance Among Nosocomial Escherichia coli Klebsiella spp., and Enterobacter spp. Isolates Collected in Russia within 2003-2007

Nosocomial bacterial Isolates collected within 2003-2004 (n=411) and 2005-2007 (n=422) were highly resistant to cephalosporins III-IV and antibacterials of other groups (aminoglycosides, fluoroquinolons, chloramphenicol, and co-trimoxazole). Genes encoding TEM, SHV, CTX-M, OXA-2, and AmpC types of beta-lactamases (BLs) in the E.coli, Klebsiella spp., and Enterobacter spp. isolates were detected using polymerase chain reaction (PCR). Prevalent CTX-M-type BLs were detected in 85% of the E.coli, 87% of the Klebsiella spp., and 38% of the Enterobacter spp. isolates of the first strain collection and in 94% of the E.coli, 91% of the Klebsiella spp., and 38% of the Enterobacter spp. isolates of the second one. Genes belonging to three subtypes of bla_CTX-M genes were identified: bla_CTX-M-1 (228 bla_CTX-M-15 and six bla_CTX-M-3 of the first strain collection; 275 bla_CTX-M-15, three bla_CTX-M-3, and one bla_CTX-M-22 of the second one), bla_CTX-M-2 (one bla_CTX__M_₅ of the first strain collection and one bla_CTX-M-2 of the second one), bla_CTX-M-9 (17 bla_CTX-M-14 and one bla_CTX-M-9 of the first strain collection; seven bla_CTX-M-14 and one bla_CTX-M-9 of the second one). Three isolates of the first strain collection and one isolate of the second one carried two genes belonging to two different subtypes i. e. bla_CTX-M-15 and bla_CTX-M-14 simultaneously. The bacterial isolates had high levels of associative resistance to ciprofloxacin, co-trimoxazole, gentamicin, amikacin, and chloramphenicol associated with the resistance gene cassettes aadA1, aadA2, aadA5, aadB, aacA4, aac(6)Ib; dfrA1, dfrA5, dfrA12, dfrA17, cmlA1, ereA2, and catB8 in the class 1 integrons and the resistance gene cassettes dfrA1, sat1, and aadA1 in the class 2 integrons.

nosocomial isolates, antibacterial resistance, bla_CTX__Mgenes, integrons, gene cassettes

1. Paterson D. L., Bonomo R. A. Extended-spectrum ß-lactamases: a clinical update. Clin Microbiol Rew 2005; 18: 4: 657-686.

2. Canton R., Novais A., Valverde A. et al. Prevalence and spread of extended -spectrum ß-lactamase-producing Enterobacteriaceae in Europe. Clin Microbiol Infect 2008; 14: 1: 144-153.

3. Rossolini G. M., D'Andrea M. M., Mugnaioli C. The spread of CTX-Mtype extended-spectrum ß-lactamases. Ibid 2008; 14: 1: 33-41.

4. Baraniak A., Fiett J., Sulikowska A., Hryniewicz W., Gniadkowski M. Countrywide spread of CxX-M-3 extended-spectrum beta-lactamaseproducing microorganisms of the family Enterobacteriaceae in Poland. Antimicrob Agents Chemother 2002; 46: 151-159.

5. Novais A., Canton R., Valverde A. et al. Dissemination and persistence of blaCTX-M-9 are linked to class 1 integrons containing CR1 associated with defective transposon derivatives from xn402 located in early antibiotic resistance plasmids of IncH12, IncP1-a, and IncFI groups. Ibid 2006; 50: 2741-2750.

6. Quinteros M., Radice M., Gardella N. et al. Extended-spectrum ß-lactamases in Enterobacteriaceae in Buenos Aires, Argentina, public hospitals. Ibid 2003; 47: 9: 2864-2867.

7. Canton R., Coque T. M. The CTX-M ß-lactamase pandemic. Curr Opinion Microbiol 2006; 9: 466-475.

8. 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: 3724-3732.

9. Сидоренко C. В, Березин A. Г., Иванов Д. В. Молекулярные механизмы устойчивости грамотрицательных бактерий семейства Enterobacteriaceae к цефалоспориновым антибиотикам. Антибиотики и химиотер 2004; 49: 3: 3-13.

10. Fursova N. K., Kruglov A. N., Abaev I. V. et al. Spreading of beta-lactamase genes among nosocomial isolates collected from Moscow clinics. Clin Microbiol Infect 2006; 12: 4: 1351.

11. NCCLS/CLSI. 2006. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically, 5th ed. Document M7-A5. Clinical and Laboratory Standards Institute, Wayne, PA.

12. http://www.eucast.org/fileadmin/src/media/PDFs/EUCAST_files/ Disk_test_documents/EUCAST_breakpoints_v1.0_20091221.pdf

13. Методические указания МУК 4.2.1890-04 «Определение чувствительности микроорганизмов к антибактериальным препаратам». Утверждены Главным государственным санитарным врачом РФ Г.Г. Онищенко 04.03.2004 г.

14. Эйдельштейн М. В. Выявление бета-лактамаз расширенного спектра у грамотрицательных бактерий с помощью фенотипических методов. Клин микробиол антимикроб химиотер 2001; 3: 2: 183-189.

15. Rasheed J. K., Jay C., Metchock B., Berkowitz F. et al. Evolution of extended-spectrum beta-lactam resistance (SHV-8) in a strain of Escherichia coli during multiple episodes of bacteremia. Antimicrob Agents Chemother 1997; 41: 3: 647-653.

16. Oliver A., Weigel L. M., Rasheed J. K. et al. Mechanisms of decreased susceptibility to cefpodoxime in Escherichia coli. Antibiotics and Chemother 2002; 46(12): 3829-3836.

17. Pérez-Pérez F. J., Hanson N. D. Detection of plasmid-mediated AmpC beta-lactamase genes in clinical isolates by using multiplex PCR. J Clin Microbiol 2002; 40: 2153-2162.

18. Robicsek A., Strahilevitz J., Sahm D. F. et al. qnr Prevalence in ceftazidime-resistant Enterobacteriaceae isolates from the United States. Antimicrob Agents Chemother 2006; 50: 8: 2872-2874.

19. Machado E., Cantón R., Baquero F. et al. Integron content of extended-spectrum-beta-lactamase-producing Escherichia coli strains over 12 years in a single hospital in Madrid, Spain. Ibid 2005; 49: 5: 1823-1829.

20. Skurnik D., Le Menac'h A., Zurakowski D. et al. Integron-associated antibiotic resistance and phylogenetic grouping of Escherichia coli isolates from healthy subjects free of recent antibiotic exposure. Ibid 2005; 49: 7: 3062-3065.

21. Jiang X., Ni Y., Jiang Y., Yuan F. et al. Outbreak of infection caused by Enterobacter cloacae producing the novel VEB-3 beta-lactamase in China. J Clin Microbiol 2005; 43: 2: 826-831.

22. Amber R. P. The structure of ß-lactamases. Philos Trans R Soc Lond (Biol.) 1980; 289: 321-331.

23. Fernandez-Cuenca F., Rodriguez-Martinez J. M., Martinez-Martinez L., Pascual A. In vivo selection of Enterobacter aerogenes with reduced susceptibility to cefepime and carbapenems associated with decreased expression of a 40 kDa outer membrane protein and hyperproduction of AmpC beta-lactamase. Int J Antimicrob Agents 2006; 27: 6: 549-552.

24. Rodriguez-Martinez J. M., Velasco C., Garcia Iet al. Mutant prevention concentrations of fluoroquinolones for Enterobacteriaceae expressing the plasmid-carried quinolone resistance determinant qnrA1. Antimicrob Agents Chemother. 2007; 51: 6: 2236-2239.