• Brindusa COPACIANU Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași
  • Cristina TUCHILUS Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași
  • Antonia POIATA Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași
  • Luminita Smaranda IANCU Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași


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

Author Biographies

Brindusa COPACIANU, Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași


Facultatea de Medicinã
Disciplina de Microbiologie

Cristina TUCHILUS, Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași

Facultatea de Medicinã
Disciplina de Microbiologie

Antonia POIATA, Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași

Facultatea de Medicinã
Disciplina de Microbiologie

Luminita Smaranda IANCU, Universitatea de Medicină și Farmacie ”Gr. T. Popa” Iași

Facultatea de Medicinã
Disciplina de Microbiologie


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