Dortet Laurent, Poirel Laurent, Errera Caroline, Nordmann Patrice
INSERM U914 Emerging Resistance to Antibiotics, Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France.
INSERM U914 Emerging Resistance to Antibiotics, Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France Medical and Molecular Microbiology, Department of Medicine, Faculty of Science, University of Fribourg, Fribourg, Switzerland.
J Clin Microbiol. 2014 Jul;52(7):2359-64. doi: 10.1128/JCM.00594-14. Epub 2014 Apr 23.
Multidrug-resistant Acinetobacter baumannii isolates, particularly those that produce carbapenemases, are increasingly reported worldwide. The biochemically based Carba NP test, extensively validated for the detection of carbapenemase producers among Enterobacteriaceae and Pseudomonas spp., has been modified to detect carbapenemase production in Acinetobacter spp. A collection of 151 carbapenemase-producing and 69 non-carbapenemase-producing Acinetobacter spp. were tested using the Carba NP test and a modified Carba NP protocol (the CarbAcineto NP test) in this study. The CarbAcineto NP test requires modified lysis conditions and an increased bacterial inoculum compared to those of the original Carba NP test. The Carba NP test detects metallo-β-lactamase producers but failed to detect the production of other carbapenemase types among Acinetobacter spp. In contrast, the newly designed CarbAcineto NP test, which is rapid and reproducible, detects all types of carbapenemases with a sensitivity of 94.7% and a specificity of 100%. This cost-effective technique offers a reliable and affordable technique for identifying carbapenemase production in Acinetobacter spp., which is a marker of multidrug resistance in those species. Its use will facilitate the recognition of these carbapenemases and prevent their spread.
多重耐药鲍曼不动杆菌分离株，尤其是那些产碳青霉烯酶的菌株，在全球范围内的报道日益增多。基于生化反应的Carba NP试验已被广泛验证用于检测肠杆菌科细菌和假单胞菌属中的碳青霉烯酶生产者，现经修改用于检测不动杆菌属中的碳青霉烯酶产生情况。本研究使用Carba NP试验和一种改良的Carba NP方案（CarbAcineto NP试验）对151株产碳青霉烯酶和69株不产碳青霉烯酶的不动杆菌属菌株进行了检测。与原始的Carba NP试验相比，CarbAcineto NP试验需要修改裂解条件并增加细菌接种量。Carba NP试验能检测出金属β-内酰胺酶生产者，但无法检测出不动杆菌属中其他类型碳青霉烯酶的产生。相比之下，新设计的CarbAcineto NP试验快速且可重复，能检测出所有类型的碳青霉烯酶，灵敏度为94.7%，特异性为100%。这项具有成本效益的技术为鉴定不动杆菌属中的碳青霉烯酶产生提供了一种可靠且经济实惠的方法，而碳青霉烯酶产生是这些菌株多重耐药的一个标志。其应用将有助于识别这些碳青霉烯酶并防止其传播。
