革兰阴性菌碳青霉烯酶快速检测的方法研究

Research on rapid detection of carbapenemases in gram-negative bacteria

目的通过Carba NP试验对革兰阴性菌产生的碳青霉烯酶进行快速检测,了解临床产碳青霉烯酶的革兰阴性菌的临床分布及耐药特征,并验证CarbaNP试验准确性,为临床合理使用抗菌药物提供理论依据。方法选取医院2013年10月-2014年10月检出1 135株革兰阴性菌,利用Carba NP比色法对其中90株多耐药菌产碳青霉烯酶进行检测,并通过改良Hodge试验,亚胺培南-EDTA(乙二胺四乙酸)双纸片协同实验等方法验证其准确性、特异性。结果肺炎克雷伯菌、鲍氏不动杆菌主要来自呼吸道标本,共693株,占61.06%,铜绿假单胞菌主要来自痰液及烧伤创面脓汁,共425株,占37.44%,1 135株革兰阴性菌筛选出多耐药菌为90株,占7.93%,将90株多耐药的菌株经Carba NP法检测出产碳青霉烯酶株22株。结论 Carba NP试验用于检测碳青霉烯酶操作简单、快速、灵敏、费用低廉、特异性强,可有助于提高产碳青霉烯酶革兰阴性菌的检出率和抗菌药物的合理使用水平。

OBJECTIVE To understand the clinical distribution and drug resistance of carbapenemase-producing gram-negative bacteria via rapid detection of carbapenemases through Carba NP test and verify the accuracy of the CarbaNP test so as to provide theoretical basis for reasonable clinical use of antibiotics.METHODS A total of 1135 strains of gram-negative bacteria that were isolated from Oct 2013 to Oct 2014 were enrolled in the study,then the carbapenemases produced by 90 strains of multidrug-resistant bacteria was detected by using Carba NP colorimetric method,and the accuracy and specificity of the Carba NP colorimetric method were verified by means of modified Hodge test and imipenem-EDTA（ethylenediaminetetraacetic acid）double disk synergy test.RESULTS Totally 693 strains of Klebsiella pneumoniae and Acinetobacter baumannii were isolated from respiratory tract specimens,accounting for 61.06%;totally 425 strains of Pseudomonas aeruginosa were isolated from sputum and burn wound pus,accounting for 37.44%.Totally 90 strains of multidrug-resistant bacteria were screened out from the 1 135 strains of gram-negative bacteria,accounting for 7.93%,and 22 strains of carbapenemase-producing bacteria were identified among the 90 strains of multidrug-resistant bacteria via the Carba NP test.CONCLUSIONThe Carba NP assay is simple,rapid,sensitive,low-cost,and high-specificity in the detection of carbapenemase,and it may help to raise the detection rate of carbapenemase-producing gram-negative bacteria and improve the level of reasonable use of antibiotics.