Wide dissemination of GES-type carbapenemases in Acinetobacter baumannii isolates in Kuwait

Acinetobacter baumannii is an opportunistic pathogen that is an important source of nosocomial infections. Production of extended-spectrum β-lactamases (ESBLs) of the GES type in A. baumannii has been increasingly reported, and some of these GES-type enzymes possess some carbapenemase activity. Our aim was to analyze the resistance determinants and the clonal relationships of carbapenem-nonsusceptible A. baumannii clinical isolates recovered from hospitals in Kuwait. A total of 63 isolates were analyzed, and all were found to be positive for bla(GES)-type genes. One isolate harbored the bla(GES-14) gene encoding an ESBL with significant carbapenemase activity, whereas the other isolates harbored the bla(GES-11) ESBL gene. Thirty-three isolates coharbored the bla(OXA-23) and bla(GES-11) genes. Analyses of the genetic locations indicated that the bla(GES-11/-14) genes were plasmid located. It is noteworthy that the bla(OXA-23) and bla(GES-11) genes were colocated onto a single plasmid. Nine different pulsotypes were observed among the 63 isolates. This study showed the emergence of GES-type ESBLs in A. baumannii in Kuwait, further suggesting that the Middle East region might be a reservoir for carbapenemase-producing A. baumannii.