Abdalhamid Baha, Albunayan Samar, Shaikh Alaa, Elhadi Nasreldin, Aljindan Reem
Department of Pathology and Laboratory Medicine, King Fahad Specialist Hospital, PO Box 15215, Dammam, Saudi Arabia.
Department of Clinical Laboratory Science, College of Applied Medical Sciences, University of Dammam, PO Box 2435, AlKhobar, Saudi Arabia.
J Med Microbiol. 2017 Sep;66(9):1286-1290. doi: 10.1099/jmm.0.000504. Epub 2017 Aug 18.
Enterobacteriaceae encoding plasmid-mediated AmpC (pAmpC) β-lactamases confer resistance to the third generation cephalosporins. pAmpC association with extended spectrum β-lactamases (ESBLs), plasmid-mediated quinolone resistance (PMQR) and aminoglycoside modifying enzymes (AMEs) is well documented. There are limited data regarding the epidemiology and clinical significance of pAmpC in Saudi Arabia. This study aimed to determine the prevalence of pAmpC and its coexistence with ESBLs, PMQR and AMEs in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis isolates in Saudi hospitals from January to December 2015.
The VITEK 2 system was used for organism identification and susceptibility testing. PCR and sequencing were used to detect pAmpC, ESBL, AME and PMQR genes.
Out of 3625 isolates of E. coli, K. pneumoniae and P. mirabilis, 200 cefoxitin-resistant isolates were identified, making the prevalence of cefoxitin resistance 5.5 % (200/3625). CMY-2 and DHA were detected in 24 and 12 isolates, respectively. The prevalence of pAmpC was 1 % (36/3625). In several isolates, pAmpC β-lactamases were associated with PMQR genes including aac(6')-Ib-cr and qnrB and/or with AMEs including aacA4, aacC2, aadA1, aphA6, armA and rmtB genes. No ESBLs were detected in pAmpC β-lactamase-harbouring isolates.
To our knowledge, this is the first study determining the prevalence of pAmpC β-lactamases and their association with PMQR and/or AME genes in Saudi Arabia and the Gulf States. CMY-2 is the most prevalent pAmpC β-lactamase in this study. These data emphasize the importance of surveillance studies and implementation of antimicrobial stewardship programmes to reduce infections caused by such resistant organisms.
编码质粒介导的AmpC（pAmpC）β-内酰胺酶的肠杆菌科细菌对第三代头孢菌素具有耐药性。pAmpC与超广谱β-内酰胺酶（ESBLs）、质粒介导的喹诺酮耐药性（PMQR）和氨基糖苷类修饰酶（AMEs）的关联已有充分记录。关于沙特阿拉伯pAmpC的流行病学和临床意义的数据有限。本研究旨在确定2015年1月至12月沙特医院分离的大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌中pAmpC的流行率及其与ESBLs, PMQR和AMEs的共存情况。
采用VITEK 2系统进行细菌鉴定和药敏试验。采用PCR和测序技术检测pAmpC、ESBL、AME和PMQR基因。
在3625株大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌中，鉴定出200株对头孢西丁耐药的菌株，头孢西丁耐药率为5.5%（200/3625）。分别在24株和12株菌株中检测到CMY-2和DHA。pAmpC的流行率为1%（36/3625）。在几株菌株中，pAmpCβ-内酰胺酶与包括aac(6')-Ib-cr和qnrB在内的PMQR基因和/或与包括aacA4、aacC2、aadA1、aphA6、armA和rmtB基因在内的AMEs相关。在携带pAmpCβ-内酰胺酶的菌株中未检测到ESBLs。
据我们所知，这是第一项确定沙特阿拉伯和海湾国家pAmpCβ-内酰胺酶流行率及其与PMQR和/或AME基因关联的研究。CMY-2是本研究中最常见的pAmpCβ-内酰胺酶。这些数据强调了监测研究和实施抗菌药物管理计划以减少此类耐药菌引起感染的重要性。
