Consequences of switching from a fixed 2 : 1 ratio of amoxicillin/clavulanate (CLSI) to a fixed concentration of clavulanate (EUCAST) for susceptibility testing of Escherichia coli

Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands; Department of Medical Microbiology and Infection Control, Bronovo Hospital, The Hague, The Netherlands; Diaconessenhuis, Leiden, The Netherlands; Izore, Centre for Infectious Diseases Friesland, Leeuwarden, The Netherlands; The Regional Laboratory of Public Health, Haarlem, The Netherlands; Department of Microbiology, Medical Center Alkmaar, Alkmaar, The Netherlands