Comparison of Broth Microdilution, Agar Dilution, and Etest for Susceptibility Testing of Doripenem against Gram-Negative and Gram-Positive Pathogens

The susceptibility of 513 clinical isolates to doripenem was determined by broth microdilution, agar dilution, and Etest. Overall agreements for Etest and agar dilution MIC values compared to reference broth microdilution at +/-1 log(2) dilution were 88% and 94%, respectively. Etest MIC values demonstrated 98% agreement within +/-2 log(2) dilutions compared to the reference broth microdilution method.