Rao Mohan, Rashid Fairuz A, Shukor Surianti, Hashim Rohaidah, Ahmad Norazah
Bacteriology Unit, Infectious Disease Research Centre, Institute for Medical Research, Ministry of Health, Kuala Lumpur, Malaysia.
Infectious Disease Research Centre, National Institute of Health, Ministry of Health, Shah Alam, Malaysia.
Can J Infect Dis Med Microbiol. 2020 Apr 2;2020:5021064. doi: 10.1155/2020/5021064. eCollection 2020.
The spread of carbapenem-resistant (CrAb) is gaining worldwide attention. The spread of this pathogen is largely due to its ability to acquire various resistance genes of intrinsic and extrinsic origins that confer unpredictable susceptibility to -lactams. The aim of this study was to analyze -lactamase genetic compositions of CrAb in Malaysia.
Whole-genome sequencing (WGS) was carried out on 13 CrAb isolates from clinical samples in Malaysia from 2011 to 2016.
Endotracheal aspirate was the dominant clinical sample source ( = 6), and only one isolate was obtained from wound swab. A total of 6 sequence types (STs) of the Oxford scheme were identified, including 4 reported STs and 2 novel STs. Eleven isolates were classified into clonal complex 92 (CC92/ICII), among which ST195 and ST208 were the most prevalent STs. All 13 CrAb isolates harbored multiple -lactamase genes. ( = 13) and ( = 11) were the dominant carbapenemase gene families found in these isolates. All isolates harbor , , and genes. ( = 7), ( = 3), ( = 1), and ( = 1) are amongst other -lactamase genes found in this study. IS was found upstream to ( = 13), ( = 1), and ( = 11). All isolates had IS (mobile genetic element) upstream to the genes. All isolates were positive for Tn and Tn but were negative for Tn.
Most of the isolates were grouped under the CC92 clonal complex which belongs to international clonal lineage 2. These findings predict that carriage of carbapenem-resistant genes possibly constitutes the underlying basis of high level of international clone II prevalence. Therefore, molecular surveillance and antimicrobial stewardship are essential in implementing policies to prevent and control the spread of CrAb in hospital settings.
耐碳青霉烯类鲍曼不动杆菌（CrAb）的传播正引起全球关注。这种病原体的传播很大程度上归因于其获取多种内在和外在来源抗性基因的能力，这些基因赋予了对β-内酰胺类药物不可预测的敏感性。本研究的目的是分析马来西亚CrAb的β-内酰胺酶基因组成。
对2011年至2016年从马来西亚临床样本中分离出的13株CrAb进行全基因组测序（WGS）。
气管内吸出物是主要的临床样本来源（n = 6），仅从伤口拭子中获得1株分离株。共鉴定出牛津分型方案的6种序列类型（STs），包括4种已报道的STs和2种新的STs。11株分离株被归类为克隆复合体92（CC92/ICII），其中ST195和ST208是最常见的STs。所有13株CrAb分离株均携带多个β-内酰胺酶基因。blaOXA-23（n = 13）和blaNDM（n = 11）是这些分离株中发现的主要碳青霉烯酶基因家族。所有分离株均携带blaTEM、blaSHV和blaCTX-M基因。blaVIM（n = 7）、blaIMP（n = 3）、blaPER（n = ）和blaGES（n = 1）是本研究中发现的其他β-内酰胺酶基因。在blaOXA-23（n = 13）、blaNDM（n = 1）和blaCTX-M（n = 11）上游发现了插入序列（IS）。所有blaNDM分离株在基因上游均有IS（移动遗传元件）。所有分离株Tn1546和Tn2均为阳性，但Tn552为阴性。
大多数分离株归属于属于国际克隆谱系2的CC92克隆复合体。这些发现预示着耐碳青霉烯类基因的携带可能构成国际克隆II高流行率的潜在基础。因此，分子监测和抗菌药物管理对于实施预防和控制医院环境中CrAb传播的政策至关重要。
