"All-in-one-plate" E-test and disk diffusion susceptibility co-testing for multiresistant Acinetobacter baumannii.

Multiresistant Acinetobacter baumannii requires ancillary manual susceptibility testing with the E-test and disk diffusion when tested with the VITEK-2 system (bioMérieux, Marcy l'Etoile, France). In the study presented here, the E-test and disk diffusion were combined in a single plate, and the method was verified by comparing categorical agreement of combined and control plates. There were no very major, major or minor errors, and similar results were obtained for all ten representative bacterial strains used as controls. Co-testing is thus feasible, accurate and reproducible, and it merits evaluation with other bacterial species.