Tavakoly Talayeh, Jamali Samar, Mojtahedi Ali, Khan Mirzaei Mohammadali, Shenagari Mohammad
Department of Microbiology, Rasht Branch, Islamic Azad University, Rasht, Iran.
Cellular and Molecular Research Center, Faculty of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
Cell Mol Biol (Noisy-le-grand). 2018 Feb 28;64(3):40-44. doi: 10.14715/cmb/2018.64.3.7.
Klebsiella pneumoniae is a Gram-negative bacterium which causes several human infections. Treatment of infections related to K. pneumoniae has become problematic, because of increasing trend of extended spectrum β-lactamases producing (ESBLs) strains. The present study was aimed to detect the prevalence of ESBL-producing Klebsiella spp. and KPC-2, CMY-2 and OXA-48 β-lactamase encoding genes in clinical isolates of Klebsiella spp. isolated from hospitalized patients. In this cross-sectional study carried out from February to August 2014, 144 isolates of Klebsiella spp. were collected from different clinical specimens in hospitals in the North of Iran. Klebsiella isolates were identified using standard microbiological procedure. Antimicrobial susceptibility patterns were determined using disk diffusion method in accordance with CLSI recommendation. The presence of antibiotic resistance genes were investigated by PCR method. Among 144 Klebsiella spp., 118 isolates were identified as K. pneumoniae and 26 isolates as Klebsiella oxytoca. Antibiotic susceptibility test showed the most resistance rates were against amoxicillin (96.5%) and ampicillin (95.8%). On the other hand, the most effective antibiotic was revealed to be imipenem with resistance rate of 4.9% (Table 2). Among 144 isolated Klebsiella strains, 57 cases (39.6%) were ESBL producers. The OXA-48 and KPC-2 genes were not detected among Klebsiella spp. during the present study, but 21.1% of isolates contained CMY-2 gene. This is the first report of CMY-2 gene detection in Klebsiella spp. in Iran. The homology between CMY-2 genes identified in isolates from Northern Iran and in other countries showed the wide dispersion of this gene around the world.
肺炎克雷伯菌是一种革兰氏阴性菌，可引发多种人类感染。由于产超广谱β-内酰胺酶（ESBLs）菌株的数量呈上升趋势，与肺炎克雷伯菌相关感染的治疗已成为难题。本研究旨在检测从住院患者中分离出的肺炎克雷伯菌临床分离株中产ESBL的克雷伯菌属以及KPC-2、CMY-2和OXA-48β-内酰胺酶编码基因的流行情况。在这项于2014年2月至8月开展的横断面研究中，从伊朗北部医院的不同临床标本中收集了144株克雷伯菌属分离株。使用标准微生物学程序鉴定克雷伯菌分离株。根据美国临床和实验室标准协会（CLSI）的建议，采用纸片扩散法测定抗菌药物敏感性模式。通过聚合酶链反应（PCR）方法研究抗生素耐药基因的存在情况。在144株克雷伯菌属中，118株分离株被鉴定为肺炎克雷伯菌，26株分离株为产酸克雷伯菌。抗生素敏感性试验显示，耐药率最高的是阿莫西林（96.5%）和氨苄西林（95.8%）。另一方面，最有效的抗生素是亚胺培南，耐药率为4.9%（表2）。在144株分离的克雷伯菌菌株中，57例（39.6%）为ESBL产生菌。在本研究期间，未在克雷伯菌属中检测到OXA-48和KPC-2基因，但21.1%的分离株含有CMY-2基因。这是伊朗首次报道在克雷伯菌属中检测到CMY-2基因。在伊朗北部分离株和其他国家鉴定出CMY-2基因之间的同源性表明该基因在全球广泛传播。
