A collection of 201 Escherichia coli strains isolated from urine of patients in a Tunisian hospital between January 2006 and July 2008 was studied. Microbial identification was done by conventional methods, and antibiotic susceptibility with disk diffusion method was performed according to the Clinical Laboratory and Standards Institute guidelines. Detection of extended-spectrum beta-lactamase (ESBL) was performed by double-disk synergy test (DDST) and identification was done by PCR and sequencing. ESBL-producing isolates were subjected to molecular typing by random amplified polymorphic DNA (RAPD) and ST131 detection by PCR. Four phylogenetic groups (A, B1, B2 and D), 18 virulence genes and CTX-M group were individualized using PCR. Statistical analysis was done by Pearson χ2 test and Mann-Whitney U test. The strains were recovered primarily from urology (28%), maternity (19%) and medicine (16%) wards. Antibiotic resistance rates were ampicilin (72.1%), nalidixic acid (41.8%), ciprofloxacin (38.8%), gentamicin (23.9%) and cefotaxime (17.4%). Thirty-one of cefotaxime-resistant isolates (n = 35) had a positive DDST and harboured bla CTX-M-15 gene. Twenty of them (64.5%) belonged to the ST131 clone and showed the same RAPD DNA profile. Ciprofloxacin- and cotrimoxazole-susceptible isolates were significantly associated with phylogenetic group B2, whereas isolates that were resistant to these molecules were associated with B1 and D phylogenetic groups, respectively. Virulence genes were significantly more frequent among ciprofloxacin- and cotrimoxazole-susceptible strains than those resistant to these antibiotics. However, CXT-M-15-producing isolates were associated with many virulence genes. Isolates concomitantly susceptible to the three antimicrobials agents (ciprofloxacin, cefotaxime and cotrimoxazole) were significantly associated with group B2 and high virulence score, whereas isolates with resistance patterns especially those including resistance to ciprofloxacin belonged predominantly to B1 phylogroup and haboured few virulence genes. The emergence of virulent and multidrug-resistant E. coli is a concerning development that deserves close attention in our institution.

• MeSH
• antibakteriální látky farmakologie   terapeutické užití   MeSH
• beta-laktamasy genetika   metabolismus   MeSH
• fylogeneze MeSH
• genotyp * MeSH
• infekce močového ústrojí farmakoterapie   epidemiologie   mikrobiologie   MeSH
• infekce spojené se zdravotní péčí * MeSH
• infekce vyvolané Escherichia coli farmakoterapie   epidemiologie   mikrobiologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• mnohočetná bakteriální léková rezistence * MeSH
• uropatogenní Escherichia coli klasifikace   účinky léků   genetika   izolace a purifikace   MeSH
• virulence genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Tunisko MeSH