青海省青南地区鼠疫疫源地鼠疫菌最低抑菌浓度的测定

Determination of the minimum inhibitory concentration of Yersinia pestis in south area of Qinghai

目的通过测定青海省青南地区104株鼠疫菌对12种抗菌药物的最低抑菌浓度,确定青南地区鼠疫菌对这些药物的敏感性和50%最低抑菌浓度(50%minimun inhibitory concentration,MIC50)及90%最低抑菌浓度(90%minimun inhibitory concentration,MIC90),掌握常用抗生素对青南地区鼠疫菌的抑菌范围。方法根据美国临床和实验室标准协会(CLSI)药敏试验方法中的琼脂稀释法,测定氧氟沙星、硫酸卡那霉素、环丙沙星、复方新诺明(甲氧苄啶-磺胺甲恶唑)、硫酸链霉素、头孢曲松钠、盐酸壮观霉素、氨苄青霉素钠、氯霉素、头孢呋辛钠、盐酸四环素、莫西沙星共12种抗生素对104株鼠疫菌的最低抑菌浓度(minimum inhibitory concentration,MIC)。结果在104株鼠疫菌中未发现对氧氟沙星、硫酸卡那霉素、环丙沙星、复方新诺明(甲氧苄啶-磺胺甲恶唑)、硫酸链霉素、头孢曲松钠、盐酸壮观霉素、氨苄青霉素钠、氯霉素、头孢呋辛钠、盐酸四环素、莫西沙星具有单个或多个抗菌药物抗性的鼠疫菌株。12种抗菌药物就对鼠疫菌的体外抑菌活性来说,头孢曲松钠、复方新诺明、环丙沙星、氧氟沙星对所检测鼠疫菌株有较好的抑菌活性(MIC90≤0.125μg/ml),其次为莫西沙星、氨苄青霉素、头孢呋辛钠、卡那霉素、氯霉素、链霉素和四环素(0.5μg/ml≤MIC90≤4μg/ml),壮观霉素抑菌活性(MIC90≥16μg/ml)较差。结论青海省青南地区分离的104株鼠疫菌对以上抗菌药物不具有耐药性,通过监测该地区鼠疫菌株的耐药性可及时发现鼠疫耐药菌株,为临床治疗提供指导性数据。

Objective To determin the sensibility and minimum inhibitory concentration of MIC50(50%minimun inhibitory concentration)and MIC90(90%minimun inhibitory concentration)of 104 strains of Yersinia pestis in south area of Qinghai to 12 antibacterial drugs.Master the range of inhibition of commonly used antibiotics against plague bacteria.Methods According to the agar dilution method of CLSI susceptibility test,determine the minimum inhibitory concentration(MIC)of 12 antibiotics against 104 strains of Yersinia pestis,including of ofloxacin,ciprofloxacin,kanamycin,sulfamethoxazole-trimethoprim,streptomycin,ceftriaxone,spectinomycin,ampicillin,chloramphenicol,cefuroxime,tetracycline and moxifloxacin,respectively.Results None of the 104 strains of Yersinia pestis tested had single or multiple antimicrobial resistance to ofloxacin,ciprofloxacin,kanamycin,sulfamethoxazole-trimethoprim,streptomycin,ceftriaxone,spectinomycin,ampicillin,chloramphenicol,cefuroxime,tetracycline and moxifloxacin.In terms of in vitro activity of the 12 antibacterial drugs against Yersinia pestis,ceftriaxone,sulfamethoxazole-trimethoprim,ciprofloxacin and ofloxacin had showed good inhibition activity(MIC90≤0.125μg/ml),followed by moxifloxacin,ampicillin,cefuroxime,kanamycin,chloramphenicol,streptomycin and tetracycline(0.5μg/ml≤MIC90≤4μg/ml),with poor inhibitory activity of spectinomycin(MIC90≥16μg/ml).Conclusion The 104 strains of plague bacteria isolated in the south area of Qinghai were not resistant to the above antibiotics.By monitoring the drug-resistant of Yersinia pestis in this area,the resistant strain of Yersinia pestis can be found in time and provide guiding data for clinical treatment.