1988 Volume 62 Issue 7 Pages 641-651
The organisms used in this study, were isolated from various clinical materials submitted to the Central Clinical Laboratory, Teikyo University Hospital from October 1986 to March 1987. We investigated the isolation frequency of fluoroquinolones (QNLs)-resistant strains in every species and their susceptibilities to norfloxacin (NFLX), ofloxacin (OFLX), and ciprofloxacin (CPFX).
The results were as follows:
1. Of the isolated organisms, the species highly resistant frequency to QNLs were S. aureus (13.0%), S. marcescens (45.8%), and P. aeruginosa (8.7%). QNLs-resistant strains were less than 5.0% in other species.
2. QNLs-resistant S. aureus already were isolated from various clinical materials, whereas the majority of the isolates of S. marcescens and P. aeruginosa were from urine.
3. Many of the QNLs-resistant S. aureus were acquired QNLs resistance in addition to methicillin resistance.
4. QNLs-resistant S. marcescens were also resistant to multiple antibiotics and the half of them were resistant to all β-lactams and aminoglycosides (AGs) used in this study.
5. In contrast with the above species, QNLs-resistant P. aeruginosa were sensitive to either β-lactamsorAGs.
6. Susceptibilities of QNLs-resistant strains to the above three chemically synthetic antibiotics were diferent from that of QNLs sensitive strains. furthermore, these strains could be divided into 2 groups; the one had moderate MICs near 6.25 μg/ml, the other had high MICs about 100, μg/ml. Correlations between MICs to 3 antibiotics were noted.
