title: Comparative in vitro activity of quinolones against Stenotrophomonas maltophilia.
abstract: The susceptibility of 109 Stenotrophomonas maltophilia isolates, all characterized by pulsed-field gel electrophoresis, to nine quinolones was studied. Grepafloxacin, trovafloxacin, and moxifloxacin displayed similar intrinsic activities (MIC90, 0.5 microg/ml), which were lower than those of ofloxacin and ciprofloxacin (MIC90, 4 microg/ml), norfloxacin (MIC90, 64 microg/ml), and nalidixic acid (MIC90, 32 microg/ml). Nalidixic acid was generally one- to twofold dilutions more active than norfloxacin. According to the criteria of the National Committee for Clinical Laboratory Standards (NCCLS), the percentage of isolates susceptible to ciprofloxacin (breakpoint < or = 1 microg/ml) was 76.1%. Using the NCCLS breakpoint for comparative purposes, the percentage of isolates susceptible to grepafloxacin, moxifloxacin, and trovafloxacin was 95.4, 96.4, and 96.4%, respectively. These results indicate that new quinolones may potentially be used for the management of Stenotrophomonas maltophilia infections.
authors.affiliation: Servicio de Microbiología, Hospital Ramón y Cajal, Madrid, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Valdezate
authors.forename: A
authors.initials: A
authors.lastname: Vindel
authors.forename: F
authors.initials: F
authors.lastname: Baquero
authors.forename: R
authors.initials: R
authors.lastname: Cantón
mesh_terms: D042462:4-Quinolones; D000890:Anti-Infective Agents / Q000494:pharmacology*; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D020615:Stenotrophomonas maltophilia / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D042462:4-Quinolones; D000890:Anti-Infective Agents