羊种布氏菌体外药物敏感性分析

Antibiotic susceptibility of Brucella melitensis isolates in human population of China

目的了解羊种布氏菌对常用抗生索的耐药情况及耐药机制。方法用微量稀释法对国内分离的69株羊种布氏菌进行12种抗生素(阿奇霉素、克拉霉素、环丙沙星、左氧氟沙星、莫西沙星、氧氟沙星、诺氟沙星、多西环素、利福平、头孢曲松、复方新诺明、链霉素)的耐药检测。结果除了阿奇霉素和克拉霉素外,所有羊种布氏菌对另外10种抗生素均敏感。所有菌株23SrRNA都具有单核苷酸多态性2632 T/C。结论 23SrRNA转肽酶中心点突变是羊种布氏菌耐大环内酯类耐药的机制之一。尽管布氏菌耐药尚未对布病防控构成威胁,但还需开展耐利福平监测工作。

To evaluate the antibiotic susceptibility of Brucella melitensis,in vitro activities of rifampin（RIF）,doxycycline（DOX）,ceftriaxone（CRO）,streptomycin（STR）,azithromycin（AZ）,clarithromycin（CLA）,ciprofloxacin（CIP）,levofloxacin（LEV）,moxifloxacin（MXF）,norfloxacin（NOR）,ofloxacin（OFL） and trimethoprim-sulfamethoxazole（SXT） were determined by the broth microdilution testing in accordance with the procedures recommended by the Clinical and Laboratory Standards Institute（CLSI） for slow-growing bacteria.All isolates were sensitive to tested antibiotics addition to azithromycin and clarithromycin.Partial nucleotide sequences of the 23SrRNA gene were analyzed for all isolates and single nucleotide polymorphism alterations of 2632 T/C were found.The results suggested that macrolides resistance is associated with spontaneous point mutations in the 23S rRNA gene affecting II and V domains as well as the peptidyl transferase center or increased efflux.