In-vitro antimicrobial activity of a carbapenem, MK-0826 (L-749,345) and provisional interpretive criteria for disc tests

The in-vitro activity of MK-0826, a new oral carbapenem, was compared with that of imipenem by broth microdilution susceptibility tests against 545 bacterial isolates. MK-0826 had significantly greater activity against Enterobacteriaceae and poorer activity against Pseudomonas aeruginosa and many Gram-positive species. MK-0826 disc diffusion tests were also performed according to the NCCLS procedure and tentative interpretive criteria were determined far possible susceptible MIC breakpoints of less than or equal to 4.0 and less than or equal to 2.0 mg/L.