Abstract
In order to evaluate antimicrobial activity of norfloxacin (NFLX), minimum inhibitory concentration (MICs) of NFLX and control drugs were determined against clinical isolates from ocular infections that were obtained in our laboratory from July, 1993 to December, 1994.
The results are summarized as follows;
1. Compared to MIC distributions of NFLX against clinical isolates from ocular infections studied in 1986 and 1987, the MIC80 of NFLX against Corynebacterium spp.,Enterobacter spp.,Serratia spp.,Burkholderia cepacia, Flavobacterium spp., Alcaligenes spp. increased 8 times.
Almost all of NFLX-resistant strains among them were ofloxacin (OFLX)-resistant, new quinolones resistant strains, and a part of them were aminoglycosides, β-lactams-resistant as well, thus all of these strains were multiple drug resistant.
2. MIC of NFLX against Pseudomonas aeruginosa were lower than that of OFLX.
3. NFLX showed strong antimicrobial activities against so-called “particular bacteria” including Staphylococcus aureus subsp. aureus, Moraxella spp.,Haemophilus spp., and P. aeruginosa from ocular infections. And MIC80 of NFLX against these bacteria was 0.05-1.56μg/ml. We observed that NFLX eye drops was administered so that concentrations above the MIC against these clinical isolates were maintained.
