PMQR genes have also been increasingly reported [5, 6]. To date, at least three types of PMQR determinants, namely qnr families, aac(6′)-Ib-cr and quinolone efflux pump (qepA and oqxAB) have been extensively described in E. coli [3, 5, 6]. In particular, qnr genes have been frequently detected among isolates producing ESBLs [6]. Additionally, a close association between aac(6′)-Ib-cr and CTX-M-15, an ESBL that has emerged worldwide, has been reported by many epidemiological studies
[6]. Recent studies in Egypt have reported a high prevalence of CTX-M-15 encoding genes among different E. coli clones in community and hospital settings [7, 8]. The aim of this study was STA-9090 datasheet to investigate the molecular epidemiology and resistance
determinants pattern of cephalosporin resistant E. coli isolates identified from cancer patients in Cairo, Egypt in 2009–2010. A retrospective analysis of E. coli isolates from clinical samples was performed at the National Cancer Institute, Cairo, Egypt, from January 2009 to June 2010. Identification and antimicrobial susceptibility testing of gram-negative isolates had been performed in the microbiology laboratories PLX3397 datasheet of the hospitals of origin by routine methods. Thirty-two of 73 viable isolates (43.8%) were selected after ESBL production screening according to the following MIC breakpoints: cefotaxime, ≥8 mg/L; ceftazidime, ≥2 mg/L and aztreonam, ≥8 mg/L [9]. Duplicate isolates from the same patient with indistinguishable susceptibility patterns were excluded. Basic demographic and clinical data were
obtained from the databases of the microbiology laboratories. Because the study consisted of a retrospective review of routine microbiological data that were analyzed anonymously, approval by the Ethics Committee and informed consent were not required. buy Paclitaxel Minimum inhibitory concentrations of amoxicillin–clavulanic acid, cefotaxime, ceftazidime, imipenem, meropenem, gentamicin and ciprofloxacin of the 32 selected isolates were assessed by E-test (Biomérieux, Marcy l’Etoile, France). Assignment of E. coli phylogenetic groups was performed by the triplex PCR assay described by Clermont et al. [10]. Clonal relationships were established by rep-PCR amplification using the DiversiLab Escherichia fingerprinting kit (BioMérieux) according to the manufacturer’s instructions [11]. Rep-PCR products were detected and sized using microfluidic LabChips placed on an Agilent 2100 bioanalyzer (Agilent Technologies, Diegem, Belgium). DNA fragment patterns were then analyzed by using Pearson correlation coefficient pairwise pattern matching and the UPGMA clustering algorithm. Representative E. coli isolates of the four rep-PCR clusters, unclustered phylogroup D isolates and two additional isolates of special epidemiological interest were characterized by MLS) using the Achtman typing scheme (mlst.ucc.ie/mlst/dbs/Ecoli) according to the protocols published on the website.