Susceptibility profiles of 99 Bacteroides fragilis strains for 9 antimicrobial agents
were defined by using an agar dilution method. The isolates were uniformly susceptible
to imipenen and metronidazole. All isolates were resistant to ampicillin. The resistance
rates to amoxicillin/clavulanate, cefoxitin, cefotaxime, chloramphenicol, clindamycin
and tetracycline were 3.0, 12.1, 15.1, 1.0, 18.2 and 75.7%, respectively. Sixteen
strains showed reduced susceptibility to metronidazole (MIC 2-4 mg/L) but none had
nim genes using PCR. All strains were also investigated for the presence of cepA,
cfiA, cfxA, ermF and tetQ genes by PCR methodology and 92.9, 4.9, 24.2, 2 and 64.6%
of the strains were respectively found positive. These results reflect the importance
of surveys of susceptibility profiles and the relevance of detecting major genetic
determinants to monitor the dissemination of these genes.