This study investigated carbapenem resistance among Acinetobacter baumannii isolated from respiratory specimens. Epidemiological relationship of the isolates was also evaluated. In this study, 81 respiratory specimens of A. baumannii from AL Zahra Hospital were confirmed by phenotypic and genotypic methods. Antimicrobial susceptibility was performed by disc diffusion method. Carbapenem resistance genes were identified by PCR. The isolates were typed by RAPD-PCR and multilocus sequence typing (MLST) methods. All isolates were resistant to imipenem and 80 isolates to meropenem. Frequency of oxacillinase genes was as follows: blaOXA-23 gene was positive in 74 (91.3%), blaOXA-24 gene in 50 (61.7%) and blaOXA-58 was not found in any isolates. On the other hand 22 (27.2%) isolates contained blaIMP-1, 3 (3.7%) isolates contained blaIMP-2 gene, 5 (6.2%) isolates contained blaVIM-1, 4 (5%) isolates had blaVIM-2 and none of the isolates had blaSIM-1 gene. RAPD-PCR typing identified 16 different patterns, with one pattern being the most frequent one in 26 isolates. In MLST 6 different sequence types were identified, the most predominant being ST2 belonging to clonal complex 2. The results of this study showed high resistance to carbapenems as well as high abundance of oxacillinase genes.

中文翻译：

---

伊朗碳青霉烯类耐药鲍曼不动杆菌 ST2 的调查。


本研究调查了从呼吸道标本中分离出的鲍曼不动杆菌对碳青霉烯类抗生素的耐药性。还评估了分离株的流行病学关系。本研究通过表型和基因型方法对来自 AL Zahra 医院的 81 份鲍曼不动杆菌呼吸道标本进行了证实。抗菌药物敏感性采用纸片扩散法进行。通过PCR鉴定碳青霉烯类抗性基因。通过 RAPD-PCR 和多位点序列分型 (MLST) 方法对分离株进行分型。所有分离株均对亚胺培南耐药，80 个分离株对美罗培南耐药。苯唑西林酶基因频率如下：blaOXA-23基因阳性74株（91.3%），blaOXA-24基因阳性50株（61.7%），blaOXA-58基因在任何分离株中均未发现。另一方面，22 个 (27.2%) 分离株含有 blaIMP-1，3 个 (3.7%) 个分离株含有 blaIMP-2 基因，5 个 (6.2%) 个分离株含有 blaVIM-1，4 个 (5%) 个分离株含有 blaVIM-2，但没有的分离株具有 blaSIM-1 基因。 RAPD-PCR 分型鉴定出 16 种不同的模式，其中一种模式是 26 种分离株中最常见的一种。在 MLST 中，鉴定出 6 种不同的序列类型，最主要的是属于克隆复合体 2 的 ST2。这项研究的结果显示对碳青霉烯类的高抗性以及高丰度的苯唑西林酶基因。