Faculty of Medicine, Department of Clinical and Chemical Pathology, Cairo University, Cairo, Egypt.
Faculty of Medicine, Department of Clinical Pathology, Beni-Suef University, Beni-Suef, Egypt.
PLoS One. 2021 Jun 24;16(6):e0251508. doi: 10.1371/journal.pone.0251508. eCollection 2021.
Acinetobacter baumannii (A. baumannii) represents a global threat owing to its ability to resist most of the currently available antimicrobial agents. Moreover, emergence of carbapenem resistant A. baumannii (CR-AB) isolates limits the available treatment options. Enzymatic degradation by variety of ß-lactamases, have been identified as the most common mechanism of carbapenem resistance in A. baumannii. The alarming increase in the prevalence of CR-AB necessitates continuous screening and molecular characterization to appreciate the problem. The present study was performed to assess the prevalence and characterize carbapenemases among 206 CR-AB isolated from various clinical specimens collected from different intensive care units at Kasr Al-Aini Hospital. All isolates were confirmed to be A. baumannii by detection of the blaOXA-51-like gene. Molecular screening of 13 common Ambler class bla carbapenemases genes in addition to insertion sequence (IS-1) upstream OXA-23 were performed by using four sets of multiplex PCR, followed by identification using gene sequencing technology. Among the investigated genes, the prevalence of blaOXA-23, and blaOXA-58 were 77.7%, and 1.9%, respectively. The ISAba1 was detected in 10% of the blaOXA-23 positive isolates. The prevalence of metallo-β-lactamases (MBLs) studied; blaNDM-1, blaSPM, blaVIM, blaSIM-1 were 11.7%, 6.3%, 0.5%, and 0.5% respectively. One of class A; bla KPC was detected in 10.7% of the investigated isolates. blaOXA-24/40, blaIMP, blaGES, blaVEB and blaGIM were not detected in any of the studied isolates. Moreover, 18.4% of the isolates have shown to harbor two or more of the screened bla genes. We concluded that the most prevalent type of ß-lactamases genes among CR-AB isolates collected from Egyptian patients were blaOXA-23 followed by blaNDM-1 and blaKPC.
鲍曼不动杆菌（A.baumannii）能够抵抗目前大多数可用的抗菌药物，因此对全球构成威胁。此外，碳青霉烯类耐药鲍曼不动杆菌（CR-AB）分离株的出现限制了可用的治疗选择。多种β-内酰胺酶的酶促降解已被确定为鲍曼不动杆菌碳青霉烯类耐药的最常见机制。CR-AB 患病率的惊人增加需要不断进行筛选和分子特征分析，以了解这一问题。本研究旨在评估从不同重症监护病房收集的各种临床标本中分离的 206 株 CR-AB 中碳青霉烯酶的流行率和特征。通过检测 blaOXA-51 样基因，所有分离株均确认为鲍曼不动杆菌。通过使用四组多重 PCR 对 13 种常见的 Ambler 类 bla 碳青霉烯酶基因以及插入序列（IS-1）上游的 OXA-23 进行分子筛选，然后使用基因测序技术进行鉴定。在所研究的基因中，blaOXA-23 和 blaOXA-58 的流行率分别为 77.7%和 1.9%。在 blaOXA-23 阳性分离株中检测到 10%的 ISAba1。研究的金属β-内酰胺酶（MBLs）；blaNDM-1、blaSPM、blaVIM、blaSIM-1 的流行率分别为 11.7%、6.3%、0.5%和 0.5%。在研究的分离株中检测到一种 A 类；blaKPC 占 10.7%。blaOXA-24/40、blaIMP、blaGES、blaVEB 和 blaGIM 在任何研究的分离株中均未检测到。此外，18.4%的分离株携带两种或两种以上筛选的 bla 基因。我们得出结论，从埃及患者中分离的 CR-AB 分离株中最常见的β-内酰胺酶基因类型是 blaOXA-23，其次是 blaNDM-1 和 blaKPC。
