CERCETÃRI PRIVIND PRODUCEREA DE BETA-LACTAMAZE CU SPECTRU EXTINS LA TULPINI DE ENTEROBACTERII
Aim: To evaluate the susceptibility
of extended spectrum beta-lactamase (ESBL) producing organisms among Escherichia coli and
Klebsiella pneumoniae, isolated between January-October 2009 from hospital and community.
Materials and methods: From 611 enterobacteria strains, for 112 strains (E. coli, n=84 and
K. pneumoniae, n=28), the ESBL phenotypic confirmation was performed with double disk
test (DDT) and the replacement disk method. The minimum inhibitory concentrations (MICs)
for next antimicrobial agents tested: ceftazidime, cefotaxime, ceftriaxone, cefepime, cefpirome,
imipenem, meropenem, ertapenem, moxifloxacin, gatifloxacin, levofloxacin, ofloxacin were
performed by agar dilution method. Resistance rates were reported using the Clinical Laboratory
Standard Institute (CLSI) breakpoints for the fully susceptible category; moderately
susceptible isolates were classified as resistant. K. pneumoniae ATCC 700603 and E. coli
ATCC 25922 were used for quality control. Results: Resistance rates for ceftazidime,
cefotaxime, ceftriaxone and aztreonam among tested strains were very high: 84.5%, 100%,
100% and 96.4% for E. coli and 98.8%, 98.8%, 97.6% and 89.2% for K. pneumoniae, with
the MIC90 values > 256 mg/L for either antimicrobial tested agent. The MICs for fourth
generation cephalosporins ranges from 4 mg/L to 512 mg/L. The MICs for tested quinolones
were > 2 mg/L for 89.2% strains. Using breakpoint for susceptibility, all isolates were
sensitive to ertapenem, imipenem and meropenem. Conclusions: We noticed a high resistance
rate for ceftazidime, cefotaxime, ceftriaxone and aztreonam. In this study, carbapenems demonstrated
the highest degree of activity
Rev 2005; 18: 657-686.
2. Livermore DM. Carbapenemases. J Antimicrob Chemother 1992; 29: 609-616.
3. Moland ES, Kim SY, Hong SG, Thomson KS. Newer beta-lactamases: clinical and laboratory
implications, part I. Clin Microbiol Newsletter 2008; 30 (10): 71-77.
4. Clinical and Laboratory Standards Institute. Methods for dilution antimicrobial susceptibility tests
for bacteria that grow aerobically. Approved standard M07-A8 and Informational Supplement
M100-S19, 2009; vol. 29. National Committee for Clinical Laboratory Standards, Wayne, Pa.
5. Poiata A, Tuchiluº C, Grigore L et al. Enterobacteriaceae resistance in Eastern Romania: trends for 40 years
period. 9th Scientific Meeting of the European Society of Chemotherapy Infectious Diseases, 2002; 18.
6. Azap OK, Arslan H, Serefhanoglu K et al. Risk factor for extended-spectrum beta-lactamase
positivity in uropathogenic Escherichia coli isolated from community-acquired urinary tract
infections. Clin Microbiol Infect 2010; 16(2): 149-151.
7. Hal Jones C, Tuckman M, Keeney D, Ruzin A, Bradford P. Characterization and sequence
analysis of extended-spectrum beta-lactamase-encoding genes from Escherichia coli, Klebsiella
pneumoniae and Proteus mirabilis isolates collected during tigecycline phase 3 clinical trials.
Antimicrob Agents Chemother 2009; 53: 465-475.
8. Rodriguez-Bano J, Nava MD, Romero I, et al. Epidemiology and clinical features of infectious
caused by extended-spectrum beta-lactamase-producing Escherichia coli in nonhospitalized patients.
J Clin Microbiol 2004; 42: 1089-1094
9. Mugnaioli C, Luzzaro F, De Luca F et al. CTX-M-type extended-spectrum beta-lactamasess in
Italy: molecular epidemiology of an emerging countrywide problem. Antimicrob Agents Chemother
2006, 50: 2700-2706.
10. Pournaras S, Ikonomidis A, Sofianou D et al. CTX-M-type beta-lactamases affect community
Escherichia coli treatment, Greece. Emerg Infect Dis 2004: 10: 1163-1164.
11. Woodford N, Ward ME, Kaufmann ME et al. Community and hospital spread of E. coli producing
CTX-M extended-spectrum beta-lactamases in the UK. J Antimicrob Chemother 2004; 54: 735-743.
Once an article is accepted for publication, MSJ requests a transfer of copyrights for published articles.
COPYRIGHT TRANSFER FORM FOR
REVISTA MEDICO-CHIRURGICALĂ A SOCIETĂȚII DE MEDICI ȘI NATURALIȘTI DIN IAȘI /
THE MEDICAL-SURGICAL JOURNAL OF THE SOCIETY OF PHYSICIANS AND NATURALISTS FROM IASI
We, the undersigned authors of the manuscript entitled
warrant that this manuscript, which is submitted for publication in the REVISTA MEDICO-CHIRURGICALĂ, has not been published and it is not under consideration for publication in another journal.
- we give the consent for publication in the REVISTA MEDICO-CHIRURGICALĂ, in printed and electronic format and we transfer unconditioned and complete the copyright of this manuscript to the REVISTA MEDICO-CHIRURGICALĂ, in the event of its acceptance.
- the manuscript does not break the intellectual property rights of any other person.
- we have read the submitted version of the manuscript and we are fully responsible for the content.
Names and signatures of authors / copyright owners (the following sequence is the authorship of the article):
N.B. All the authors must sign this form