[Antibacterial activity of lamoxactam in combination with penicillin, ampicillin and amoxicillin against clinical strains of Enterococci, group B Streptococci and Listeria].

The antibacterial activity of moxalactam-penicillin combinations was studied against clinical isolates of Enterococci (20 strains), group B Streptococci (10), Listeria (3) and Enterobacteriaceae (10), using a microtiter checkerboard (FIC index, FBC index). Combinations of moxalactam (MX) with penicillin G, ampicillin or amoxicillin were usually synergistic against Enterococci and Listeria but with high MX concentrations. Against group B Streptococci, penicillin-MX combinations were synergistic (40%) or additive (60%) with MX concentrations easily achievable in the CSF.