RESUMEN

Twenty-five extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli clinical isolates from Rio de Janeiro, Brazil were characterized by isoelectric focusing, PCR and sequencing of bla(ESBL) genes, plasmid-mediated quinolone resistance determinants, phylogenetic groups, replicon typing, pulsed-field electrophoresis, and multilocus sequencing typing. Twenty-three (92%) ESBL-producing E. coli isolates were positive for bla(CTX-M) genes, aac(6')-Ib-cr, and qnrB. Genetic relatedness of ESBL producers clustered seven (28%) CTX-M-15-producing isolates as sequence type (ST)410, clonal complex (CC) 23, and two (8%) as clone O25-ST131. Our results illustrate the predominance of phylogroup A (52%), ST410 (CC 23) and CTX-M-15 among ESBL-producing E. coli isolates from hospitals in Rio de Janeiro.

Asunto(s)

Escherichia coli/enzimología , beta-Lactamasas/biosíntesis , beta-Lactamasas/genética , Brasil , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Escherichia coli/clasificación , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Genotipo , Humanos , Focalización Isoeléctrica , Tipificación de Secuencias Multilocus , Plásmidos , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , beta-Lactamasas/química , beta-Lactamasas/aislamiento & purificación