Bacteroides fragilis 군 세균의 cefepime 등 항균제에 대한 감수성

Abstract

Background : Bacteroides fragilis group (BFG) organisms, the most commonly isolated anaerobes from clinical specimens, are more frequently resistant to antirmcrobial agents than other anaerobes. The aim of this study was to determine the susceptibility of BFG organisms to various antimicrobial agents including cefepime.

Methods : Antimicrobial susceptibility of 136 BFG organisms, whch were isolated in 1995 and 1996 from various clinical materials and consisted of 88 B. fragilis, 28 B. thetaiotaomicron, 7 B. ovatus, 7 B. miformis, 4 B. distasonis. 2 B. vulgatus, were tested by the NCCLS agar dilution method using Wilkins Chalgren agar. The plates were incubated in an anaerobic chamber for 48 h before reading the results.

Results : The resistance rates to cefotaxime were 3382% depending on the species. The resistance rates to cefotetan varied markedly dependmg on the species of the BFG organisms and the resistance rates were 9% for B. fragilis. 79% for B. thetaiotaomicron and 85% for other BFG species. The resistance rates were higher than those in 1994. The resistance rates to cefoxitin were: B. fragilis. 1% ; B. thetaiotaomicron, 14%; other BFG species, 10%, although no isolate showed resistance to cefoxitin in 1994. The MIC90S of the cefepime were >128 ㎍/mL against all BFG organisms, and the resistance rates were 85-100%. No lsolates were found to be resistant to imipenem, chloramphenicol and metronidazole.

Conclusion : The increased resistance to cefotaxhe, cephamych and chdarnycun indicates that routine antimicrobial susceptibility test of these drugs is needed before using the drugs, and the high MIC value to cefepirne suggests that it would not be useful for the treatment of anaerobic infection.