摘要
目的了解嗜麦芽窄食单胞菌临床分离株的耐药特征及其机制。方法采用美国临床实验室标准化委员会(NCCLS)推荐的纸片扩散法,测定4年中初次分离的88株嗜麦芽窄食单胞菌(SMA)对阿米卡星、氨曲南和头孢他啶等12种抗生素的耐药特征。聚合酶链反应(PCR)法分别扩增抗庆大霉素和阿米卡星的7种氨基糖苷修饰酶基因(AME)。双纸片协同试验检测超广谱β-内酰胺酶(ESBLs),协同筛选法测定金属β-内酰胺酶(MBLs)。结果4年中嗜麦芽窄食单胞菌对12种抗生素的耐药率分别是:米诺环素0%～9.7%、替卡西林/克拉维酸12.5%～22.6%、左氧氟沙星12.5%～28.6%、多西环素18.8%～33.3%、复方磺胺甲恶唑18.8%～40%、环丙沙星50%～65.7%、头孢他啶50%～66.7%、阿米卡星54.8%～66.7%、庆大霉素75%～100%、哌拉西林81.3%～100%、氨曲南87.5%～100%和亚胺培南93.5%～100%。氨基糖苷修饰酶基因检出率分别是:aac(3)-Ⅰ和ant(4')-Ⅱ未检测到;其余5种基因中,aac(3)-Ⅱ,ant(2'')-Ⅰ,aac(6')-Ⅰ,aac(3)-Ⅲ和aac(3)-Ⅳ的检出率分别是2.3%,5.7%,8%,11.4%和11.4%。产ESBLs菌株占38.6%(34/88);产MBLs菌株占25%(22/88),同时产ESBLs和MBLs的菌株占13.6%(12/88)。结论本研究所检测的嗜麦芽窄食单胞菌多重耐药严重,耐药机制复杂,临床上应在药敏结果指导下选用合适的抗生素进行治疗。
Objective To investigate the antimicrobial resistance of clinical isolates ofStenotrophomonas matophilia （SMA） and the mechanisms of their drug resistance. Methods Disc diffusion method （NCCLS） was used to detect the resistant patterns of 88 initial SMA isolates resistant to 12 antibiotics isolated from a local hospital in the past 4 years. PCR was used to detect the 7 aminoglycosides modifying enzymes genes （AME） against amikacin and gentamicin. Metal-β-1actamases （MBLs） were screened by synergic method, and extended-spectrum β-1actamases （ESBLs） were detected by double-disk synergy test. Results The resistance rates of the SMA isolates were 0%-9.7% to minocycline, 12.5%-22.6% to ticarcillin-clavulanie acid, 12.5%-28.6% to levofloxacin, 18.8%-33.3% to doxycycline, 18.8%-40% to sulfamethoxazole compound, 50%-65.7% to ciprofloxacin, 50%-66.7% to cehazindme, 54.8%-66.7% to amikacin, 75%-100% to gentamicin, 81.3%-100% to piperacillin, 87.5%-100% to aztreonam and 93.5%-100% to imipenem. Aac （3）-Ⅰ and ant （4＇）-Ⅱ were not detected in these strains. The positive rates of the other 5 AME genes ofaac（3）-Ⅱ, ant（2＂）-Ⅰ, aac（6＇）-Ⅰ, aac（3）-Ⅲ, aac（3）-Ⅳ were 2.3%, 5.7%, 8%, 10%, and 10%, respectively. SMA strains producing ESBLs were found at the rate of 38.6%; 25% of the strains were MBL-producing, and 13.6% produced both ESBLs and MBLs. Conclusion Most of the SMAs we isolated are multidrug-resistant through various mechanisms. The choice of antibiotics should be made according to the susceptibility results.
出处
《南方医科大学学报》
CAS
CSCD
北大核心
2009年第5期852-855,共4页
Journal of Southern Medical University
基金
国家自然科学基金(30700686)
广东省医学科研基金(A20066367)
