Journal of Antimicrobial Chemotherapy (1989) 23, 209-219
© 1989 The British Society for Antimicrobial Chemotherapy
research-article |
In-vitro activity of lomefloxacin in comparison with pefloxacin and ofloxacin
aService de Médecine et Laboratoire d'Investigation Clinique H. J. Tagnon, Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles rue Héger-Bordet, 1, B-1000, Bruxelles bLaboratoire de Microbiologie, Fondation Reine Elisabeth, Hôpital Universitaire Brugmann Bruxelles cLaboratoire de Microbiologie, Akademisch Ziekenhuis, Vrije Universiteit Brussel Bruxelles, Belgium
Received 12 August 1988; accepted 12 October 1988
The in-vitro activity of lomefloxacin (SC 47111, NY-198) was investigated by the determination of MICs in agar and in broth, of MBCs in broth, of killing curves and of the duration of the post-antibiotic effect. MICs measured in broth and in agar were almost identical. Lomefloxacin was two- to eight-fold less active against Grain-positive bacteria than ofloxacin. Its activity against Staphylococcus aureus was independent of resistance to penicillin and oxacillin. The activity of lomefloxacin, ofloxacin and pefloxacin was poor against JK corynebacteria. Enterobacteriaceac, Aeromonas spp., Haemophilus influenzae, Neisseriaceac and Campylobacter jejuni were highly susceptible to the three quinolones investigated. Non-fermenting Gram-negative bacilli were less susceptible. MBCs were within one dilution of the corresponding MICa. The killing rate was very high against Gram- negative bacilli (2·54·0 log cfu/ml reduction in 2 h) whereas it was low against Gram-positive bacteria (0·51·0 log cfu/ml reduction in 2 h). Emergence of resistance was not observed. The duration of the post-antibiotic effect with Gram- negative bacilli depended on the strain and species (median: 0·91·5 h). The post-antibiotic effect was insignificant with Staph. aureus.