First Description of IncX3 Plasmids Carrying blaOXA-181 in Escherichia coli Clinical Isolates in Burkina Faso
First Description of IncX3 Plasmids Carrying blaOXA-181 in Escherichia coli Clinical Isolates in Burkina Faso
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DOI：
10.1128/aac.00147-16
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发表时间：
2016-05-01
影响因子：
4.9
通讯作者：
Godreuil, Sylvain
中科院分区：
文献类型：
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作者：
Ouedraogo, Abdoul-Salam;Compain, Fabrice;Godreuil, Sylvain
产碳青霉烯酶肠杆菌科（CPE）在全球范围内的报道越来越多。在西非和东非，关于CPE流行病学的少数研究强调了喀麦隆（NDM-4）、肯尼亚（NDM-1）、塞拉利昂（Vim和DIM-1）、塞内加尔（OXA-48）和坦桑尼亚（KPC、IMP、OXA-48、Vim和NDM）中碳青霉烯酶的鉴定（1）。虽然blaOXA-48基因在北非广泛传播，但blaOXA-48衍生物在非洲很少报道。事实上，blaOXA-163在埃及仅检测到两次，blaOXA-181（OXA-48的点突变类似物）在南非仅检测到一次（1）。在这里，我们描述了前四例大肠杆菌携带blaOXA-181基因在布基纳法索。四个。大肠杆菌菌株（表1）从布基纳法索瓦加杜古的两家医院的四名患者中分离。使用Etest（bioMérieux）测定的碳青霉烯MIC分别为1 - 1.5 mg/L、0.125 - 0.75 mg/L和0.25 - 0.5 mg/L（厄他培南、多利培南和亚胺培南）（表1）。3例患者在菌株分离前接受抗生素治疗（表1）。没有患者报告最近到布基纳法索境外旅行。针对最常见的超广谱β-内酰胺酶（ESBL）和碳青霉烯酶编码基因（2，3）的多重PCR和DNA测序显示，4种分离株中存在blaCTX-M-15和blaOXA-181。未检出其他碳青霉烯酶编码基因（对应于NDM、Vim、IMP和KPC）。多位点序列分型（MLST）（http：//bigsdb.org）。web.巴斯德。fr/）的序列分析表明，这4个菌株均属于新的序列型（ST）ST 692。肠杆菌重复基因间共有序列PCR（ERIC-PCR）（4）模式（见补充材料中的图S1）和基于7个多态性位点（6-1-5-8-3-5-1;见表1）分析确定的可变数目串联重复（VNTR）（5）模式证实了4个E.大肠杆菌菌株。然而，对医疗记录的审查表明，这四名病人在不同的机构（医院和病房）住院。虽然患者之间没有关系或住房共享，但这些数据支持在这些医院或一般社区中传播的相同多药耐药克隆感染的假设。通过碱裂解提取质粒DNA，随后如前所述通过凝胶电泳进行分析（6）。使用参考质粒RP 4（54 kb）、pCFF 04（85 kb）和pIP 173（126.8 kb）进行比较分析，并显示ca. 120 KB和CA。54 kb的核苷酸序列。coli J53作为受体在各种条件下均未成功。使用QIAprep Spin Miniprep试剂盒（Qiagen）提取质粒DNA，并通过电穿孔转移到E. coliDH10B（Invitrogen，Cergy-Ponnige，France）。携带blaOXA-181的转化体显示厄他培南和亚胺培南的MIC分别为0.38至0.5 mg/L和0.5至0.75 mg/L。通过质粒松弛酶基因分型（7）和基于PCR的复制子分型（8）的分析分别鉴定了转化体中的IncX 3型松弛酶和ColE型复制起始基因。转化子的碱裂解和随后的电泳表明这些基因由ca. 54 kb质粒。最近在大肠杆菌中发现了携带blaOXA-181的IncX 3质粒。以质粒pOXA 181_EC 14828为模板设计引物，对4株大肠杆菌及其转化子进行PCR图谱分析。
Carbapenemase-producing Enterobacteriaceae (CPE) have been increasingly reported worldwide. The few studies available on CPE epidemiology in West and East Africa highlight the identification of carbapenemases in Cameroon (NDM-4), Kenya (NDM-1), Sierra Leone (VIM and DIM-1), Senegal (OXA-48), and Tanzania (KPC, IMP, OXA-48, VIM, and NDM)(1). Although blaOXA-48 genes are widely spread in North Africa, blaOXA-48 derivatives have been rarely reported in Africa. Indeed, blaOXA-163 was detected only twice in Egypt andblaOXA-181 (a point mutant analogue of OXA-48) only once in South Africa (1). Here, we describe the first four cases of Escherichia coli carrying the blaOXA-181 gene in Burkina Faso. FourE. colistrains (Table 1) were isolated from four patients in two hospitals in Ouagadougou, Burkina Faso. Carbapenem MICs, determined using the Etest (bioMérieux), were 1 to 1.5 mg/liter, 0.125 to 0.75 mg/liter, and 0.25 to 0.5 mg/liter for ertapenem, doripenem, and imipenem, respectively (Table 1). Three patients received antibiotics before strain isolation (Table 1). None of the patients reported recent travel outside Burkina Faso. Multiplex PCR and DNA sequencing targeting the most prevalent extendedspectrum-β-lactamase (ESBL)-and carbapenemase-encoding genes (2, 3) revealed the presence of blaCTX-M-15 and of blaOXA-181 in the four isolates. No other carbapenemase-encoding gene (corresponding to NDM, VIM, IMP, and KPC) was detected. Multilocus sequence typing (MLST)(http://bigsdb. web. pasteur. fr/) showed that the four strains belonged to new sequence type (ST) ST692, which is described here for the first time. Enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR)(4) patterns (see Fig. S1 in the supplemental material) and the variable-number tandem-repeat (VNTR)(5) profile determined on the basis of analysis of 7 polymorphic loci (6-1-5-8-3-5-1; see Table 1) confirmed the genetic links among the four E. coli strains. However, the review of medical records indicated that the four patients were hospitalized in different structures (hospitals and wards). Although there was no relationship or housing shared between the patients, these data support the hypothesis of infections by the same multidrug-resistant clone circulating in these hospitals or in the general community. Plasmid DNA was extracted by alkaline lysis and subsequently analyzed by gel electrophoresis as previously described (6). Comparative analysis was carried out using reference plasmids RP4 (54 kb), pCFF04 (85 kb), and pIP173 (126.8 kb) and showed two different plasmids of ca. 120 kb and ca. 54 kb, respectively, in each strain.Mating experiments performed using azide-resistant E. coli strain J53 as a recipient under various conditions were unsuccessful. Plasmid DNA was extracted using a QIAprep Spin Miniprep kit (Qiagen) and transferred by electroporation intoE. coliDH10B (Invitrogen, Cergy-Pontoise, France). The blaOXA-181-carrying transformants showed ertapenem and imipenem MICs of 0.38 to 0.5 mg/liter and 0.5 to 0.75 mg/liter, respectively. Analysis by plasmid relaxase gene typing (7) and PCR-based replicon typing (8) identified IncX3-type relaxase and ColE-type replication initiation genes, respectively, in the transformants. Alkaline lysis of transformants and subsequent electrophoresis showed that these genes were carried by the ca. 54-kb plasmid. As a blaOXA-181-carrying IncX3 plasmid was recently identified in E. coli in China (9), PCR mapping was carried out in the four strains and their respective transformants with primers designed using plasmid pOXA181_EC14828 as the template (GenBank …