In vitro susceptibility of 4903 bacterial isolates to gemifloxacin—an advanced fluoroquinolone

Comparison of minimal inhibitory and mutant prevention drug concentrations of 4 fluoroquinolones against clinical isolates of methicillin-susceptible and -resistant Staphylococcus aureus

“…The newer fluoroquinolones (gatifloxacin, gemifloxacin, moxifloxacin) have been reported [21,22] to have enhanced (lower MIC values) actively against Gram-positive pathogens than do the other agents (ciprofloxacin, levofloxacin) and numerous investigations [33,34] have confirmed these observations reporting MIC 90 values of 0.063-0.5 mg/l for the newer agents (gatifloxacin, gemifloxacin, moxifloxacin) and 0.25-2 mg/l for the older compounds (ciprofloxacin, levofloxacin) against methicillin-susceptible strains.…”

“…Of the European isolates of MRSA, 89.5% were also ciprofloxacin resistant whereas only 8.4% of MSSA strains were resistant to ciprofloxacin [20]. The new fluoroquinolones (gatifloxacin, gemifloxacin, moxifloxacin) have been reported to have enhanced activity against Gram-positive pathogens when compared with older fluoroquinolones [21,22]. We were interested in determining whether differences in MIC values between the compounds parallel differences in mutant prevention concentrations (MPC) [23][24][25]-a novel measurement for comparing antimicrobial potency based on the likelihood of selecting for resistance when the compounds are exposed to a larger inoculum of bacteria.…”

A pilot study testing whether concentrations of levofloxacin in interstitial space fluid of soft tissues may serve as a surrogate for predicting its pharmacokinetics in lung

“…Therefore, in the present study, both parameters were calculated for free levofloxacin concentrations in lung tissue. MIC 90 s of levofloxacin against relevant pathogens causing respiratory tract infections were obtained from recent literature [17,20].…”

Good Penetration of Moxifloxacin into Human Abscesses

“…The following attempt to assess if the observed moxifloxacin concentrations might be sufficient to kill abscess-relevant bacterial pathogens at the target site is a bit speculative because complete concentration-time profiles are not available for abscesses: For moxifloxacin MIC 90 values of 0.063 mg/l were reported for Escherichia coli in the literature, and MIC 90 values of 0.125 mg/l or 1 mg/l were reported for methicillin-susceptible Staphylococcus aureus collected from different sources [14,15]. Accordingly, the reported MIC 90 of E. coli was exceeded spontaneously in all abscesses where moxifloxacin was detectable (7 of 10), whereas the MIC 90 values of methicillin-susceptible S. aureus were reached only in 5 or 3 of 10 abscesses at incision after a single dose.…”