硼酸抑制纸片扩散试验检测肺炎克雷伯菌中的KPC

检验医学 ›› 2012, Vol. 27 ›› Issue (9): 754-759.

硼酸抑制纸片扩散试验检测肺炎克雷伯菌中的KPC

严育忠¹,胡付品²,孙康德³,范惠清¹,华静¹,陆燕春⁴

1. 上海浦东新区南汇中心医院检验科，上海 201300；2. 复旦大学附属华山医院抗生素研究所，上海 200040；3. 上海交通大学医学院附属第九人民医院，上海 200011

收稿日期:2012-07-04 修回日期:2012-08-31 出版日期:2012-09-12 发布日期:2012-09-12
通讯作者: 陆燕春，联系电话：021-58022995。
作者简介:严育忠，男，1977年生，硕士，主管技师，主要从事细菌耐药性研究。
基金资助:
上海市浦东新区卫生科技项目（PW2011A-22）

Disk tests incorporating boracic acid inhibitor to detect KPC in Klebsiella pneumoniae

1. Department of Clinical Laboratory，Nanhui Central Hospital of Pudong，Shanghai 201300,China; 2. Institute of Antibiotics，Huashan Hospital，Fudan University，Shanghai 200040,China; 3. The Ninth People′s Hospital，Shanghai Jiaotong University School of Medicine，Shanghai 200011，China

Received:2012-07-04 Revised:2012-08-31 Online:2012-09-12 Published:2012-09-12

摘要/Abstract

摘要： 目的　评估利用硼酸的纸片扩散试验检测肺炎克雷伯菌中肺炎克雷伯菌碳青霉烯酶(KPC)的效能。方法　收集经基因鉴定非重复的36株产KPC肺炎克雷伯菌株；采用琼脂稀释法测定所有菌株对亚胺培南、美罗培南和厄他培南的最低抑菌浓度（MIC）值；聚合酶链反应（PCR）和DNA测序鉴定β-内酰胺酶基因型；使用标准和超过标准的2种测试菌量进行改良Hodge试验（MHT）以检测碳青霉烯酶表型；利用8种抗菌药物纸片含或不含硼酸抑制剂的纸片扩散试验检测KPC表型，以两者抑菌圈直径差值≥5 mm判定阳性结果。结果　所有36株产KPC菌株至少对1种碳青霉烯类药物耐药。MHT检测碳青霉烯酶的敏感性和特异性为97.2%和91.0%,增加菌量后的敏感性和特异性为100.0%和87.0%。利用硼酸联合头孢吡肟、亚胺培南或美罗培南的纸片扩散试验检测肺炎克雷伯菌产KPC表型，敏感性和特异性均达到100.0%。结论　硼酸联合头孢吡肟、亚胺培南或美罗培南的纸片扩散试验能检测出KPC表型，而且该方法操作简单、结果易读。

关键词: 肺炎克雷伯菌碳青霉烯酶, 纸片扩散试验, 抑制剂, 表型试验

Abstract: Objective　To evaluate the disk tests incorporating boracic acid inhibitor for the detection of Klebsiella pneumoniae carbopenem (KPC)-producing Klebsiella pneumoniae isolates. Methods　A total of 36 genetically unrelated KPC-producing Klebsiella pneumoniae isolates were determined. The minimum inhibitory concentrations(MIC) of imipenem，meropenem and ertapenem were determined by agar dilution method．Polymerase chain reaction (PCR) and DNA sequencing were used for the identification of beta-lactamase genotypes. The modified Hodge test (MHT)，using both standard and high inoculum of test organisms，was performed to detect carbopenem phenotype. The disk tests consisting of 8 antibiotics with and without boracic acid inhibitor were designed to detect KPC phenotype，and the diameter≥5 mm augmentation of inhibition zone was considered a positive result. Results　All 36 KPC-producing Klebsiella pneumoniae isolates were resistant to at least one of the 3 carbopenems. The sensitivity and specificity of MHT were 97.2% and 91.0% for the detection of carbopenems，and they were 100.0% and 87.0% when a high inoculum was employed. For disk tests using cefepime，imipenem or meropenem with and without boracic acid detecting KPC phenotype in Klebsiella pneumoniae，the sensitivity and specificity were 100.0%. Conclusions　Disk tests incorporating boracic acid inhibitor in combination with cefepime，imipenem or meropenem may help the phenotypic detection of KPC in Klebsiella pneumoniae，and are very easy to perform and interpret.

严育忠;胡付品;孙康德;范惠清;陆燕春;华　静. 硼酸抑制纸片扩散试验检测肺炎克雷伯菌中的KPC[J]. 检验医学, 2012, 27(9): 754-759.

YAN Yuzhong;HU Fupin;SUN Kangde;FAN Huiqing;LU Yanchun;HUA Jing . Disk tests incorporating boracic acid inhibitor to detect KPC in Klebsiella pneumoniae[J]. , 2012, 27(9): 754-759.

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