加硼酸或氯唑西林的改良Hodge试验检测肠杆菌科细菌碳青霉烯酶的研究  

Study on the Detection of Carbapenemase among Enterobacteriaceae Using Modified Hodge Test by Incorporating Boronic Acid or Cloxacillin

作　　者：王卫萍[1] 严留佳[1] 施德仕[1] 邵海枫[1] 范明[1] 黄梅[1] 

机构地区：[1]南京军区南京总医院临床中心实验科,南京210002

出　　处：《现代检验医学杂志》2011年第6期28-32,36,共6页Journal of Modern Laboratory Medicine

基　　金：南京军区医药卫生科研基金（07M089）.

摘　　要：目的 探讨加硼酸或氯唑西林的改良Hodge试验在碳青霉烯酶类药物敏感性降低的细菌中检测碳青霉烯酶的临床应用价值.方法 收集2009年～2010年南京军区总医院对碳青霉烯酶类药物敏感性降低（亚胺培南、美罗培南或厄他培南的MIC≥2 μg/ml）的肠杆菌科细菌65株;采用琼脂倍比稀释法测定其对亚胺培南、美罗培南和厄他培南的MIC;通过改良Hodge试验和加硼酸或氯唑西林的改良Hodge试验检测碳青霉烯酶;采用PCR检测多种β-内酰胺酶基因,并对PCR阳性产物测序鉴定.结果 65株临床分离菌中,53株菌对亚胺培南不敏感（MIC＞4 μg/ml）,51株菌对美罗培南不敏感（MIC＞4 μg/ml）,58株菌对厄他培南不敏感（MIC＞2 μg/ml）.65株菌中38株改良Hodge试验阳性,包括7株弱阳性和31强阳性;33株加硼酸或氯唑西林的改良Hodge试验阳性,包括改良Hodge试验弱阳性2株和强阳性31株.经过对菌株进行β-内酰胺酶基因PCR和测序,发现加硼酸或氯唑西林的改良Hodge试验阳性菌株均携带blaKPC-2;32株阴性菌株均未携带碳青霉烯酶酶基因,但其中5株改良Hodge试验弱阳性菌株携带blampC/blaESBL.结论 加硼酸或氯唑西林的改良Hodge试验可快速、有效地区分改良Hodge试验的真、假阳性,是检测肠杆菌科细菌碳青霉烯酶的简便可靠方法,适用于临床微生物实验室.Objective To consider the reliability of modified Hodge test （MHT） by incorporating boronie acid or cloxacillin to detect carbapenemases among Enterobacteriaceae with decreased susceptibility to carbapenems. Methods 65 Enterobacteriaceae isolates with decreased susceptibility to earbapenems（MIC of imipenem,meropenem or ertaponem was ≥2 μg/ml） were collected from Nanjing General hospital＇s from 2009 to 2010. MICs of imipenem,meropenem and etapenem were determined by agar dilution method. Carbaponemases were detected by MHT and the modified boronie acid-or cloxaeillin-based MHT. Beta-lactamases encoding genes were detected by PCR and sequencing. Results 53 of 65 isolates were non-susceptible to imipenem（MIC〉4 μg/ml）,51 were non-susceptible to meroponem （MIC〉4 μg/ml ）and 58 were non-susceptible to ertapenem （MIC〉2 μg/ml）. 38 isolates showed positive MHT result,including 7 weak-positive results and S1 strong-positive results. 33 isolates showed positive modified boronic acid-or cloxacillin-based MHT result,including 2 weak-positive MHT results and 31 strong-positive MHT results. Through PCR detection and sequencing,all 33 isolates showing positive modi- fied boronic acid-or eloxacillin-based MHT result carried blaKPC-2. All 32 isolates with negative modified boronic acid-or cloxacillin-based MHT results didn＇t carry any earbapenemases genes, but 5 isolates showing weak-positive MHT result carry AmpCs/ESBLs genes. Conclusion Modified boronic acid-or cloxacillin-based MHT could be rapidly and effectively differentiate true and false positive MHT results. It is a simple and reliable method to detect carbapenemases and suitable for clinical microbiology laboratory.

关 键 词：碳青霉烯酶 肠杆菌科 β-内酰胺酶 硼酸 改良HODGE试验 

分 类 号：R373.13[医药卫生—病原生物学] R446.62[医药卫生—基础医学]