13株杨氏枸橼酸杆菌的黏附、细胞毒性和耐药性检测

Adhesion, cytotoxicity and antimicrobial resistance of 13 Citrobacter youngae isolates

目的了解杨氏枸橼酸杆菌(CY)的黏附、细胞毒性和耐药情况。方法对从安徽省马鞍山市腹泻病例分离到的13株CY开展黏附HEp-2细胞的检测,同时对HEp-2细胞(MOI:100)作用8 h后的乳酸脱氢酶(LDH)释放情况以及对15种抗生素的药敏实验进行分析。结果 5株CY几乎没有黏附性,黏附指数<1;6株CY具有中等黏附性,黏附指数>1,且<50;2株CY具有强的黏附性,黏附指数>50。与HEp-2细胞作用8 h后,3株菌引起的LDH释放量>20.00%,其余10株菌引起的LDH释放量均<20.00%。13株CY对环丙沙星和妥布霉素均敏感(100%),对氨苄西林和头孢唑啉的耐药率最高(92.30%)。CY1对7种抗生素耐药,属于多重耐药菌,并且具有强的细胞毒性。结论本研究共检测出3株强细胞毒性的CY和7株多重耐药的CY,建议临床关注枸橼酸杆菌的毒性和多重耐药情况。

Objective To understand the adhesion,cytotoxicity and antimicrobial resistance of Citrobacter youngae（ CY）.Methods The detection of HEp-2 cells in 13 C. youngae isolates from Maanshanwas conducted for adhesion and cytotoxicity analysis. The isolates＇ susceptibilities to 15 antibiotics were tested. Results Five C. youngae isolates showed little adhesion,with indexes 1,6 isolates showed intermediate adhesion,with adhesion indexes ranging from 1 to 50 and 2 isolates showed the strongest adhesion,with adhesion indexes 50. After 8 hours co-culturing with HEp-2 cells,3 C. youngae isolates showed LDH releasing more than 20. 00%,the remaining 10 isolates showed LDH releasing less than 20. 00%. Thirteen C. youngae isolates were sensitive to ciprofloxacin and tobramycin（ 100%）,and were highly resistant to ampicillin and cefazolin（ 92. 30%）. CY1 showing strongest adhesion and cytotoxicity was multidrug resistant,with resistance to 7 antibiotics.Conclusion In this study,we detected 3 C. youngae isolates with high cytotoxicity and 7 multidrug resistant C. youngae isolates. It is important to survey the toxicity and multidrug resistance of C. youngae in clinical practice.