Emergence of carbapenem-resistant non-baumannii species of Acinetobacter harboring a blaOXA-51-like gene that is intrinsic to A. baumannii.

The bla(OXA-51)-like gene, originally intrinsic to Acinetobacter baumannii, had been detected in two clones of Acinetobacter nosocomialis and one clone of Acinetobacter genomic species "Close to 13TU." These bla(OXA-51)-like genes, all preceded by ISAba1, were located on plasmids that might have originated with A. baumannii. The plasmid-borne ISAba1--bla(OXA-51)-like confers a high level of carbapenem resistance and affects the accuracy of using bla(OXA-51)-like detection as a tool for differentiating A. baumannii from other Acinetobacter species.