[Antibacterial activity of ciprofloxacin against fresh clinical isolates from superficial suppurative foci].

The minimum inhibitory concentrations (MICs) of 5 drugs (ciprofloxacin (CPFX), and 4 drugs used as standard) were determined to investigate antibacterial potencies of CPFX against bacterial strains isolated in 1989 from superficial suppurative foci. The clinical isolates tested included 375 strains from 11 aerobic bacterial species, and 50 strains from 2 anerobic bacterial genera (group) for a total of 425 isolates. Interpreting MIC level distributions of these drugs as the expression of antibacterial potencies, the results are as follows. 1. When activities of new-quinolone antibiotics were tested, we found that, CPFX expressed far superior antibacterial potency to ofloxacin (OFLX) and norfloxacin (NFLX) against coagulase-negative staphylococci, Enterococcus faecalis, Enterococcus faecium, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Proteus mirabilis, Proteus vulgaris, Morganella morganii, Pseudomonas aeruginosa and Peptostreptococcus spp., although the activity of CPFX against Bacteroides fragilis group was weaker than that of OFLX, and CPFX had similar activity against Staphylococcus aureus to OFLX. 2. In comparison to beta-lactam antibiotics, CPFX was inferior to amoxicillin (AMPC) against E. faecalis and inferior to AMPC and cefaclor (CCL) against Peptostreptococcus spp. Against all other bacterial species, however, CPFX expressed superior antibacterial potency to AMPC and CCL. 3. Scattered findings of low sensitivity or resistance to CPFX were observed among the S. aureus, E. faecalis, E. faecium, P. vulgaris, M. morganii, P. aeruginosa and B. fragilis (group) species, but with an exception of E. faecium, the incidence of resistance strains was low.