RESUMEN
The antimicrobial activity of a new fluoro-quinolone, lomefloxacin (NY-198, SC47111), was evaluated by standardized susceptibility testing methods at ten laboratories in Argentina. Lomefloxacin was found to be the most active drug against 1,316 recent clinical isolates compared directly to norfloxacin, co-trimoxazole, and gentamicin. Only 1.4% of Enterobacteriaceae were lomefloxacin-resistant (MIC greater than 4 micrograms/ml), and the lomefloxacin MIC90 for all staphylococci was 2 micrograms/ml, including methicillin-resistant isolates. Streptococci, enterococci, and some Pseudomonads (9% resistance) were less susceptible to lomefloxacin. Lomefloxacin was the most active against Neisseria gonorrhoeae strains compared to penicillin, cefuroxime, and spectinomycin. Among the tested Mycobacteria, only the nontuberculosis, slow growers had lomefloxacin MICs of greater than 4 micrograms/ml.