改良Hodge试验阳性肠杆菌科细菌对碳青酶烯类药物的耐药性检测方法比较

Comparison study on four methods in detecting carbapenem resistance of modified hodge-test positive enterobacteriaceae

目的:了解Hodge试验阳性菌株对碳青酶烯类抗菌药物的耐药模式和评价临床常用的4种药物敏感性试验对KPC酶介导的碳青酶烯类抗菌药物耐药性的检出率。方法:收集经改良Hodge试验筛查为阳性的59株肠杆菌科细菌,用肉汤微量稀释法、纸片扩散法、VITEK-32型全自动微生物分析仪GNS-448药敏卡和ATB半自动细菌鉴定及药敏分析仪G-5药敏卡检测亚胺培南、美罗培南和厄他培南的耐药性。结果:Hodge试验阳性菌株对亚胺培南、美罗培南和厄他培南的耐药表型模式以三者均耐药为最常见,该模式在肺炎克雷伯菌耐药表型中占59.6%,在大肠埃希菌耐药表型中占30%。纸片扩散法、肉汤微量稀释法、VITEK-32、ATB法检测亚胺培南耐药率分别为69.4%、56.0%、50.8%和18.6%,美罗培南的耐药率分别为49.3%、91.5%、56.0%和25.4%,纸片扩散法和肉汤微量稀释法对厄他培南的耐药检出率为84.7%和86.4%。结论:纸片扩散法和肉汤微量稀释法能更好的检出KPC酶介导的碳青酶烯类抗菌药物的耐药性,厄他培南可作为筛选产KPC酶菌株的指示药物。

Objective：To investigate carbapenem resistant patterns of modified Hodge-test positive Enterobacteriaceae and evaluate the rates of 4 drug sensitivity tests in detecting carbapenem resistance that mediated by KPC.Methods： Fifty-nine modified Hodge-test positive Enterobacteriaceae were collected.Resistance to imipenem,meropenem and ertapenem was determined by broth microdilution,disk diffusion,VITEK-32 and ATB.Results： In 59 modified Hodge-test positive Enterobacteriaceae,multi-resistance to imipenem,meropenem and ertapenem were the most common carbapenem resistant patterns and were 59.6% for Klebsiella pneumoniae,30% for Escherichia coli respective.The resistance to imipenem that determined by disk diffusion,broth microdilution,VITEK-32 and ATB were 69.4%,56.0%,50.8% and 18.6% respective,and the resistance to meropenem were 49.3%,91.5%,56.0% and 25.4% respective.The resistance to ertapenem determined by disk diffusion and broth microdilution were 84.7% and 86.4% respective.Conclusion： The sensitivity of disk diffusion and broth microdilution is higher than other automatic methods in the identification of KPC-mediated carbapenem resistance,and ertapenem is a more sensitive indicator than meropenem and imipenem for screening KPC-possessing isolates.