ABSTRACT
CTX-M-encoding genes from Klebsiella spp. strains isolated in 2000 and 2006 were characterized as well as their genetic environment. CTX-M-2 variants were predominant in Klebsiella pneumoniae strains, which showed a greater variability in bla(CTX-M) genes, integrons, and plasmids in 2006 when compared to strains collected in 2000. CTX-M-9-producing Klebsiella oxytoca was identified in 2000 as clonal dissemination.
Subject(s)
Drug Resistance, Bacterial , Klebsiella Infections/microbiology , Klebsiella/enzymology , Klebsiella/genetics , beta-Lactamases/genetics , Bacterial Proteins/classification , Bacterial Proteins/genetics , Brazil , DNA, Bacterial/genetics , Genes, Bacterial , Hospitals , Humans , Klebsiella/metabolism , Klebsiella oxytoca/enzymology , Klebsiella oxytoca/genetics , Klebsiella oxytoca/isolation & purification , Klebsiella pneumoniae/enzymology , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/isolation & purification , Plasmids , Polymerase Chain Reaction , beta-Lactamases/classificationABSTRACT
The present study was designed to determine the prevalence and extended-spectrum beta-lactamase (ESBL) types in clinical isolates of Klebsiella spp. at a university hospital located in the Brazilian southern region (Ribeirão Preto, São Paulo) as well as their antibiotic susceptibility and genetic profiles. This study included 147 non-repeat Klebsiella spp. isolates collected from January to June 2000, of which 23 K. pneumoniae and 8 K. oxytoca were selected as ESBL producers by using the Oxoid combination disk method and Etest ESBL strip. beta-lactamases were characterized by IEF, PCR and sequencing assays using primers for ESBL genes. Antibiotic susceptibility was evaluated by MicroScan system. Dissemination of two major clones of ESBL-producing Klebsiella spp. occurred in the hospital. According to the results obtained in this study there was a clonal spread of CTX-M-producing K. oxytoca in five clinics and dissemination of ESBL-producing K. pneumoniae in the nursery and pediatrics wards.
