Fluoroquinolone resistance among methicillin-resistant staphylococci after usage of fluoroquinolones other than ciprofloxacin in Taiwan.
The antimicrobial susceptibility to norfloxacin, ofloxacin, and ciprofloxacin of methicillin-resistant staphylococci isolated before and after the use of fluoroquinolones other than ciprofloxacin in Taiwan was studied by the agar dilution method. Before the use of fluoroquinolones, 54 isolates of methicillin-resistant Staphylococcus aureus (MRSA) and 51 isolates of methicillin-resistant coagulase-negative staphylococci (MRCNS) isolated in 1983-1985 were all susceptible to the three fluoroquinolones tested. Following the use of norfloxacin, enoxacin, and ofloxacin, the MIC90s of norfloxacin, ofloxacin, and ciprofloxacin against 46 isolates of MRSA collected during 1989-1990 increased to 64, 16, and 32 micrograms/ml, respectively, and the rates of resistant strains to these three agents were 37.0%, 30.4%, and 34.8%, respectively. The MIC90s against 42 isolates of MRCNS also increased to 64, 8, and 8 micrograms/ml, respectively, with 35.7%, 23.8%, and 33.3% resistant strains.
Chang
S C
SC
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Republic of China.
Hsieh
W C
WC
Luh
K T
KT
D000890:Anti-Infective Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D024841:Fluoroquinolones; D006801:Humans; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development; D013624:Taiwan; D013997:Time Factors
D000890:Anti-Infective Agents; D024841:Fluoroquinolones