title: Clindamycin resistance transfer in Bacteroides fragilis.
abstract: Clindamycin is one of the antimicrobial agents most commonly used against anaerobes. Resistance to clindamycin in Bacteroides fragilis has been increasing recently. Thirty strains of clindamycin-resistant (including multi-resistant) B. fragilis were collected for study of cross-resistance to beta-lactam agents and beta-lactam--beta-lactamase inhibitor and resistance transferability. Imipenem was the most active drug against these 30 isolates. Resistance to clindamycin was transferred to a recipient in 12 out of 30 donor strains by using filter-mating. Of 12 transconjugants, only three had detectable plasmids by alkaline lysis method and the remaining nine strains lacked plasmids. The transfer frequencies ranged from 10(-4) to 10(-6). The role of plasmid in the resistance transfer was not certain. However, the results suggest that non-plasmid-mediated transfer accounted for the majority of the transfers of clindamycin-resistance of B. fragilis in this study. Tetracycline resistance was co-transferred from six donors. There was no evidence of co-transference of beta-lactam resistance under the selection marker of clindamycin, beta-lactam, or both. Therefore, non-plasmid-mediated transfer may play an important role in dissemination of resistance transfer in B. fragilis in Taiwan.
authors.affiliation: Department of Laboratory Medicine, National Taiwan University Hospital, Taipei, R.O.C.
authors.forename: L J
authors.initials: LJ
authors.lastname: Teng
authors.forename: S J
authors.initials: SJ
authors.lastname: Liaw
authors.forename: K T
authors.initials: KT
authors.lastname: Luh
authors.forename: S W
authors.initials: SW
authors.lastname: Ho
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001441:Bacteroides fragilis / Q000187:drug effects* / Q000235:genetics; D002981:Clindamycin / Q000494:pharmacology*; D003227:Conjugation, Genetic; D004352:Drug Resistance, Microbial / Q000235:genetics*; D010957:Plasmids
chemical_list: D000900:Anti-Bacterial Agents; D002981:Clindamycin