Ismail Sarah Jehad, Mahmoud Suhad Saad
Department of Biotechnology, University of Baghdad, AL Mansour City, Baghdad, Iraq.
Iran J Microbiol. 2018 Apr;10(2):98-103.
Multidrug resistance and in particular, carbapenem resistant Gram-negative bacteria is spreading worldwide at an alarming rate. Among the clinically significant carbapenemases, the New Delhi Metallo-β-lactamase (NDM) is one of the most formidable. NDM efficiently hydrolyses β-lactams and is the last-resort among carbapenems. Hence, therapeutic options for NDM producer bacteria become restricted to a handful of antibiotics. The present study was undertaken to detect the prevalence of the -variants Metallo β-lactamases (MBLs) among isolates of recovered from various clinical samples of hospitalized patients in Baghdad, Iraq.
A total of 100 isolates of Gram-negative bacteria obtained from various clinical samples were subjected to antibiotic susceptibility testing by the disc-diffusion method against meropenem (10 μg), imipenem (10 μg), doripenem (10 μg), polymyxin B (10 μg), colistin (10 μg), amikacin (30 μg), gentamicin (10 μg), aztreonam (30 μg), ciprofloxacin (5 μg), levofloxacin (5 μg), ofloxacin (5 μg), cefepime (30 μg), ceftazidime (30 μg), piperacillin-tazobactam (100\10 μg), tigecycline (15 μg) and tetracycline (10 μg). The results were interpreted according to the guidelines suggested by the Clinical Laboratory Standards Institute. Presence of was detected by PCR and it was confirmed by DNA sequencing of the gene present in the isolates that exhibited carbapenem resistance.
In the present study, four isolates of carried the , three isolates harboured and one isolate harboured . All isolates were resistant to imipenem and meropenem. The carrying isolates remained susceptible to colistin and β-lactamase inhibitors piperacillin-tazobactam.
We are reporting emergence of the carrying the -variant, which exhibited resistance to imipenem and meropenem for the first time in Iraq.
多重耐药，尤其是耐碳青霉烯类革兰氏阴性菌正在全球以惊人的速度蔓延。在具有临床意义的碳青霉烯酶中，新德里金属β-内酰胺酶（NDM）是最具威胁性的一种。NDM能有效水解β-内酰胺类药物，是碳青霉烯类药物中的最后防线。因此，针对产NDM细菌的治疗选择仅限于少数几种抗生素。本研究旨在检测从伊拉克巴格达住院患者的各种临床样本中分离出的菌株中金属β-内酰胺酶（MBLs）变体的流行情况。
从各种临床样本中获得的总共100株革兰氏阴性菌，采用纸片扩散法对美罗培南（10μg）、亚胺培南（10μg）、多利培南（10μg）、多粘菌素B（10μg）、黏菌素（10μg）、阿米卡星（30μg）、庆大霉素（10μg）、氨曲南（30μg）、环丙沙星（5μg）、左氧氟沙星（5μg）、氧氟沙星（5μg）、头孢吡肟（30μg）、头孢他啶（30μg）、哌拉西林-他唑巴坦（100\10μg）、替加环素（15μg）和四环素（10μg）进行药敏试验。结果根据临床实验室标准协会建议的指南进行解读。通过PCR检测bla基因的存在，并通过对表现出碳青霉烯耐药性的分离株中存在的基因进行DNA测序来确认。
在本研究中，4株肺炎克雷伯菌携带blaNDM-1，3株携带blaIMP，1株携带blaVIM。所有分离株均对亚胺培南和美罗培南耐药。携带blaNDM-1的分离株对黏菌素和β-内酰胺酶抑制剂哌拉西林-他唑巴坦仍敏感。
我们报道了伊拉克首次出现携带blaNDM-1变体的肺炎克雷伯菌，该菌株对亚胺培南和美罗培南耐药。
