Determination of activities of levofloxacin, alone and combined with gentamicin, ceftazidime, cefpirome, and meropenem, against 124 strains of Pseudomonas aeruginosa by checkerboard and time-kill methodology.
A total of 124 Pseudomonas aeruginosa strains were tested for synergy between levofloxacin and cefpirome, ceftazidime, gentamicin, and meropenem. Checkerboards yielded synergistic fractional inhibitory concentration (FIC) indices (< or =0.5) with 25 of 496 possible combinations. All other FIC indices were >0.5 to 2 (additive or indifferent), with no antagonism. Time-kill studies with 12 strains showed that levofloxacin (0.06 to 0.5 microg/ml) was synergistic with cefpirome, ceftazidime, gentamicin, and meropenem in 10, 9, 4, and 11 strains, respectively.
Visalli
M A
MA
Department of Pathology (Clinical Microbiology), Hershey Medical Center, Pennsylvania 17033, USA.
Jacobs
M R
MR
Appelbaum
P C
PC
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002442:Ceftazidime / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D004357:Drug Synergism; D004359:Drug Therapy, Combination / Q000494:pharmacology*; D005839:Gentamicins / Q000494:pharmacology; D064704:Levofloxacin; D000077731:Meropenem; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013845:Thienamycins / Q000494:pharmacology; D013997:Time Factors; D000097572:Cefpirome
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D002442:Ceftazidime; D002511:Cephalosporins; D005839:Gentamicins; D064704:Levofloxacin; D000077731:Meropenem; D015242:Ofloxacin; D013845:Thienamycins; D000097572:Cefpirome