In vitro activity of ciprofloxacin, levofloxacin, and trovafloxacin, alone and in combination with beta-lactams, against clinical isolates of Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Burkholderia cepacia.
We tested three fluoroquinolones (ciprofloxacin, levofloxacin, and trovafloxacin), each combined with each of four beta-lactams (cefoperazone, ceftriaxone, imipenem, and meropenem) for synergy against clinical isolates of nosocomial strains of Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Burkholderia cepacia. The ciprofloxacin-beta-lactam combinations showed synergy against none or only a small fraction (7 to 10%) of the P. aeruginosa and B. cepacia isolates. Ciprofloxacin-cefoperazone, -ceftriaxone, and -meropenem were synergic against 50%, 25%, and 30% of the S. maltophilia isolates, respectively. Among the levofloxacin combinations, only those with cefoperazone and imipenem showed significant synergy, and this only against B. cepacia (50% and 30%, respectively). Trovafloxacin-cefoperazone and -imipenem showed modest synergy against P. aeruginosa (23% and 27%, respectively), as did trovafloxacin-cefoperazone and -ceftriaxone against B. cepacia (30%). The trovafloxacin-imipenem combination was synergic against all isolates of B. cepacia. Because of their synergy, the following combinations may be useful in the nosocomial setting: trovafloxacin-cefoperazone or -imipenem against P. aeruginosa; ciprofloxacin-cefoperazone, -ceftriaxone, or -meropenem against S. maltophilia; levofloxacin-cefoperazone and trovafloxacin-imipenem against B. cepacia.
Isenberg
H D
HD
Division of Microbiology, Long Island Jewish Medical Center, New Hyde Park, NY 11042, USA.
Alperstein
P
P
France
K
K
D000890:Anti-Infective Agents / Q000494:pharmacology*; D016956:Burkholderia cepacia / Q000187:drug effects*; D002939:Ciprofloxacin / Q000494:pharmacology*; D024841:Fluoroquinolones; D006801:Humans; D064704:Levofloxacin; D009287:Naphthyridines / Q000494:pharmacology*; D015242:Ofloxacin / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D014974:Xanthomonas / Q000187:drug effects*; D047090:beta-Lactams / Q000494:pharmacology*
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D009287:Naphthyridines; D047090:beta-Lactams; D002939:Ciprofloxacin; D064704:Levofloxacin; C080163:trovafloxacin; D015242:Ofloxacin