title: National survey on the susceptibility of Bacteroides Fragilis Group: report and analysis of trends for 1997-2000.
abstract: The results of a multicenter US survey using the National Committee for Clinical Laboratory Standards currently recommended methodology for measuring in vitro susceptibility of 2673 isolates of Bacteroides fragilis group species were compared from 1997 to 2000. The test panel consisted of 14 antibiotics: 3 carbapenems, 3 beta-lactam-beta-lactamase inhibitors, 3 cephamycins, 2 fluoroquinolones, clindamycin, chloramphenicol, and metronidazole. Declines in the geometric mean minimum inhibitory concentrations were seen with imipenem, meropenem, ampicillin-sulbactam, and the cephamycins. Increased geometric means were observed with the fluoroquinolones and were usually accompanied by an increase in resistance rates. Bacteroides distasonis shows the highest resistance rates among beta-lactam antibiotics, whereas Bacteroides vulgatus shows the highest resistance levels among fluoroquinolones. B. fragilis shows the lowest resistance rates for all antibiotics. All strains were susceptible to chloramphenicol and metronidazole concentrations <8 microgram/mL. The data underscore the need for species identification and continued surveillance to monitor resistance patterns.
authors.affiliation: Departments of Medicine, Community Health, and Clinical Research, Tufts-New England Medical Center, Tufts University School of Medicine, Boston, MA, USA. dsnydman@lifespan.org
authors.forename: D R
authors.initials: DR
authors.lastname: Snydman
authors.forename: N V
authors.initials: NV
authors.lastname: Jacobus
authors.forename: L A
authors.initials: LA
authors.lastname: McDermott
authors.forename: R
authors.initials: R
authors.lastname: Ruthazer
authors.forename: E J C
authors.initials: EJ
authors.lastname: Goldstein
authors.forename: S M
authors.initials: SM
authors.lastname: Finegold
authors.forename: L J
authors.initials: LJ
authors.lastname: Harrell
authors.forename: D W
authors.initials: DW
authors.lastname: Hecht
authors.forename: S G
authors.initials: SG
authors.lastname: Jenkins
authors.forename: C
authors.initials: C
authors.lastname: Pierson
authors.forename: R
authors.initials: R
authors.lastname: Venezia
authors.forename: J
authors.initials: J
authors.lastname: Rihs
authors.forename: S L
authors.initials: SL
authors.lastname: Gorbach
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001441:Bacteroides fragilis / Q000187:drug effects*; D003625:Data Collection; D024881:Drug Resistance, Bacterial / Q000502:physiology; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000592:standards
chemical_list: D000900:Anti-Bacterial Agents