淋菌臨床分離株の抗菌剤感受性の年次変化と経口セファロスポリン剤耐性機序の解析
スポンサーリンク
概要
- 論文の詳細を見る
Clinical isolates of Neisseria gonorrhoeae recovered from 462 men with gonorrhea from 1999 through 2002 were examined for minimum inhibitory concentrations (MICs) of antimicrobial agents. Ninety-one, 150, and 221 isolates were collected in 1999-2000, 2001 and 2002, respectively. The prevalence of penicillinase-producing N. gonorrhoeae was very low over 4 years, but that of chromosomally mediated resistance to penicillin G increased to 73.3 % in 2002. The prevalence of levofloxacin resistance also increased to 78.3 % in 2002. No strain with a cefixime MIC ≥ 0.5 μg/m l was isolated in 1999-2000, but 26.0 % and 30.3 % of the isolates had cefixime MICs ≥ 0.5 μg/m l in 2001 and 2002, respectively. Ceftriaxone was still active against clinical isolates over 4 years, but two isolates with a ceftriaxone MIC of 0.5 μg/m l were found in 2002. Only one spectinomycin-resistant strain was isolated in 2001. A remarkable increase of N. gonorrhoeae with decreased susceptibility to antimicrobial agents, especially fluoroquinolones and cephalosporins, was observed in 2000-2001. Among the clinical isolates recovered in 2001, 55 isolates with cefixime MICs ≥ 0.125 μg/m l and 15 isolates with cefixime MICs ≥ 0.06 μg/m l were examined for alterations in the penicillin-binding protein 2 (PBP 2) gene. A mosaic PBP 2 composed of fragments from PBP 2 of Neisseria cinera and Neisseria perflava was found in 47 isolates. This mosaic PBP 2 was significantly associated with decreased susceptibilities to penicillin and cephalosporins, especially oral cephalosporins. Pulsed-field gel electrophoresis analysis of chromosomal DNA restriction patterns revealed that most isolates with the mosaic PBP 2 were genetically similar. The emergence and increase of such strains could arise from the spread of a limited number of clones.
- 岐阜大学の論文
- 2004-03-31