ESBL-producing Enterobacteriaceae in the Northern Portugal - Antimicrobial Susceptibility and Molecular Epidemiology

摘要

Extended-spectrum β-lactamases (ESBLs) prevalence was studied in the north of Portugal, among 193 clinical isolates belonging to citizens in a district in the boundaries between this country and Spain. It were recovered some members of Enterobacteriaceae family, producing ESBL enzymes, including Escherichia coli (67.9%), Klebsiella pneumoniae (30.6%), Klebsiella oxytoca (0.5%), Enterobacter aerogenes (0.5%) and Citrobacter freundii (0.5%). The β-lactamases genes, blaTEM, blaSHV and blaCTX-M were screened by Polymerase Chain Reaction (PCR) and sequencing approaches. TEM enzymes were among the most prevalent types (40.9%) followed by CTX-M (37.3%) and then SHV (23.3%) types. Almost all ESBL-producing isolates (98.9%) were resistant to the fourth-generation cephalosporin Cefepime. Of the 193 isolates 157 (81.3%) present transferable plasmids. Molecular typing studies were performed using PCR for enterobacterial repetitive intragenic consensus (ERIC) sequences. This study reports a high diversity of genetic patterns, A to J for E. coli isolates and K to O for K. pneumoniae strains.