醫學檢驗暨生物技術學系TENG, LEE-JENELEE-JENETENGHSUEH, PO-RENPO-RENHSUEHTSAI, JUI- CHANGJUI- CHANGTSAILIAW, SHWU-JENSHWU-JENLIAWHO, SHEN-WUSHEN-WUHOLUH, KWEN-TAYKWEN-TAYLUH2009-01-202018-07-062009-01-202018-07-062002http://ntur.lib.ntu.edu.tw//handle/246246/105277Susceptibilities to 16 antimicrobial agents were determined by measurement of MICs for 344 isolates of anaerobic bacteria recovered from patients with significant infections . Resistance rates varied among antimicrobial agents and the species tested. The beta-lactams were more active in gram- positive than in gram-negative anaerobes. Resistance to meropenem was low (<1%). For beta-lactam-beta-lactamase inhibitors, piperacillin-tazobactam was most active for all species (resistance, <6%). The rates of resistance to cefoxitin (31 to 65%) and clindamycin (50 to 70%) for non- Bacteroides fragilis species of the B. fragilis group were higher than those for B. fragilis (4% resistant to cefoxitin and 33% resistant to clindamycin). Among members of B. fragilis group, Bacteroides thetaiotaomicron was the most resistant to clindamycin (70%) and cefoxitin (65%). Rates of susceptibility to imipenem and metronidazole for B.fragilis continue to be high compared to those from a previous study 10 years ago. However, resistance to metronidazole was found recently in five strains of B. fragilis. We analyzed the genetic relationships among the metronidazole-resistant B. fragilis strains by pulsed-field gel electrophoresis. The metronidazole-resistant B. fragilis strains showed genotypic heterogeneity, excluding the dissemination of a single clone.en-USBACTEROIDES-FRAGILIS GROUPANTIMICROBIAL SUSCEPTIBILITIESPORPHYROMONASMULTICENTERPREVOTELLATRENDS