Rodolphe Mérieux Laboratories, School of Pharmacy, Saint Joseph University, Beirut, Lebanon.
Animal Health Laboratory, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, Madrid, Spain.
J Glob Antimicrob Resist. 2018 Mar;12:107-112. doi: 10.1016/j.jgar.2017.09.016. Epub 2017 Oct 3.
The aim of this study was to determine the prevalence of β-lactamases in Acinetobacter spp. recovered from Lebanese patients over a 1-year period using phenotypic and molecular methods.
A total of 100 non-duplicate consecutive Acinetobacter spp. isolates were collected from various clinical specimens. Antimicrobial susceptibility testing was performed by the disk diffusion method. Susceptibility to colistin, imipenem and meropenem was determined by broth microdilution. The β-lactamase inhibitors phenylboronic acid, cloxacillin and ethylene diamine tetra-acetic acid (EDTA) were used for presumptive detection of KPC-type β-lactamase, AmpC β-lactamase and metallo-β-lactamase (MBL), respectively. Simplex PCR was conducted for molecular detection of β-lactamases. Trilocus PCR typing was performed to determine the clonality of the isolates.
Among the 100 Acinetobacter spp. isolates, 78% were resistant to imipenem and 84% to meropenem. Only one isolate was resistant to colistin by the microdilution method. Phenotypically, 23% of the isolates were presumptively diagnosed as producing extended-spectrum β-lactamase (ESBL), 15% as producing KPC and 4% MBL, whilst 5% were diagnosed as overproducing AmpC β-lactamase. The bla gene was detected in 99% of isolates, bla in 93%, bla in 77% and bla in 3%. Trilocus PCR identified 86% (82/95) of the Acinetobacter baumannii isolates as international clone II (IC II).
A high rate of carbapenem resistance, with a predominance of OXA-23-like and IC II, was shown in this study. Moreover, the inhibitor-based method was shown not to be accurate for the prediction of carbapenemases in A. baumannii.
本研究旨在通过表型和分子方法确定在黎巴嫩患者中分离的鲍曼不动杆菌属细菌在 1 年内β-内酰胺酶的流行率。
共收集了 100 份来自各种临床标本的非重复连续鲍曼不动杆菌属细菌。通过纸片扩散法进行抗菌药物敏感性测试。用肉汤微量稀释法测定多粘菌素、亚胺培南和美罗培南的敏感性。苯硼酸、氯唑西林和乙二胺四乙酸（EDTA）分别用于推定检测 KPC 型β-内酰胺酶、AmpC β-内酰胺酶和金属β-内酰胺酶（MBL）。单重 PCR 用于β-内酰胺酶的分子检测。三联 PCR 分型用于确定分离株的克隆性。
在 100 株鲍曼不动杆菌属细菌中，78%对亚胺培南耐药，84%对美罗培南耐药。只有一株对多粘菌素的微量稀释法耐药。表型上，23%的分离株被推定产超广谱β-内酰胺酶（ESBL），15%产 KPC，4%产 MBL，5%产高产 AmpC β-内酰胺酶。99%的分离株检测到 bla 基因，93%检测到 bla 基因，77%检测到 bla 基因，3%检测到 bla 基因。三联 PCR 鉴定出 86%（82/95）的鲍曼不动杆菌属细菌为国际克隆 II（IC II）。
本研究表明，碳青霉烯类耐药率较高，以 OXA-23 样和 IC II 为主。此外，抑制剂法对鲍曼不动杆菌属碳青霉烯酶的预测并不准确。
