The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang, PR China.
People's Hospital of Liandu City, Lishui, PR China.
J Med Microbiol. 2021 Jun;70(6). doi: 10.1099/jmm.0.001364.
Members of the genus are facultative anaerobic Gram-negative bacilli belonging to the [Janda 1994; 32(8):1850-1854; Arens 1997;3(1):53-57]. Formerly, were occasionally reported as nosocomial pathogens with low virulence [Pepperell 2002;46(11):3555-60]. Now, they are consistently reported to cause nosocomial infections of the urinary tract, respiratory tract, bone, peritoneum, endocardium, meninges, intestines, bloodstream and central nervous system. Among species, the most common isolates are and , while has seldom been isolated [Janda 1994; 32(8):1850-1854; Marak 2017;49(7):532-9]. Further, spp. are usually susceptible to carbapenems, aminoglycosides, tetracyclines and colistin [Marak 2017;49(7):532-9]. As is rare, only one clinical isolate, coharbouring carbapenem resistance gene and quinolone resistance gene , has been reported. To characterize a carbapenem-resistant strain from PR China coharbouring and . Three hundred and forty nonrepetitive carbapenem-resistant (CRE) strains were collected during 2011-2018. A carbapenem-resistant strain was detected and confirmed using a VITEK mass spectrometry-based microbial identification system and 16S rRNA sequencing. Minimum inhibitory concentrations (MICs) for clinical antimicrobials were obtained by the broth microdilution method. Whole-genome sequencing (WGS) was performed for antibiotic resistance gene analysis, and a phylogenetic tree of strains was constructed using the Bacterial Pan Genome Analysis (BPGA) tool. The transferability of the resistance plasmid was verified by conjugal transfer. A rare carbapenem-resistant strain (CA71) was recovered from a patient with cerebral obstruction and the sequences of 16S rRNA gene shared more than 99 % similarity with CITRO86, FDAARGOS 165. CA71 is resistant to β-lactam, quinolone and aminoglycoside antibiotics, and even imipenem and meropenem (MICs of 2 and 4 mg l respectively), and is only sensitive to polymyxin B and tigecycline. Six antibiotic resistance genes were detected via WGS, including the β-lactam genes , and , the quinolone gene , and the aminoglycoside genes . Interestingly, and coexist on an IncN1-type plasmid (pCA71-IMP) and successfully transferred to J53 via conjugal transfer. Phylogenetic analysis showed that CA71 is most similar to strain CJ25 and belongs to the same evolutionary cluster along with seven other strains. To the best of our knowledge, this is the first report of a carbapenem-resistant isolate coharbouring and .
属成员是兼性厌氧革兰氏阴性杆菌，属于 [Janda 1994;32(8):1850-1854;Arens 1997;3(1):53-57]。以前， 偶尔被报道为毒力较低的医院病原体 [Pepperell 2002;46(11):3555-60]。现在，它们被一致报道会引起尿路感染、呼吸道感染、骨骼、腹膜、心内膜、脑膜、肠道、血液和中枢神经系统的医院感染。在 属中，最常见的分离株是 和 ，而 很少被分离 [Janda 1994;32(8):1850-1854;Marak 2017;49(7):532-9]。此外， spp. 通常对碳青霉烯类、氨基糖苷类、四环素类和黏菌素敏感 [Marak 2017;49(7):532-9]。由于 很罕见，仅报告了一例临床分离株，同时携带碳青霉烯耐药基因 和喹诺酮耐药基因 。为了对来自中国的一株同时携带 和 的耐碳青霉烯 进行特征描述。在 2011 年至 2018 年期间收集了 340 株非重复的耐碳青霉烯 （CRE）菌株。使用 VITEK 质谱微生物鉴定系统和 16S rRNA 测序检测和确认了一株耐碳青霉烯的 。采用肉汤微量稀释法测定临床抗菌药物的最低抑菌浓度（MICs）。通过全基因组测序（WGS）进行抗生素耐药基因分析，并使用细菌泛基因组分析（BPGA）工具构建 菌株的系统发育树。通过接合转移验证了耐药质粒的可转移性。从一名脑阻塞患者中回收了一株罕见的耐碳青霉烯 （CA71），其 16S rRNA 基因序列与 CITRO86、FDAARGOS 165 的相似度超过 99%。CA71 对β-内酰胺类、喹诺酮类和氨基糖苷类抗生素耐药，甚至对亚胺培南和美罗培南（MIC 分别为 2 和 4 mg/L）耐药，仅对黏菌素和替加环素敏感。通过 WGS 检测到 6 个抗生素耐药基因，包括β-内酰胺基因 、 、 、喹诺酮基因 ，以及氨基糖苷基因 。有趣的是， 和 共同存在于一个 IncN1 型质粒（pCA71-IMP）上，并通过接合转移成功转移到 J53 中。系统发育分析表明，CA71 与 菌株 CJ25 最为相似，与其他 7 株菌一起属于同一进化群。据我们所知，这是首例同时携带 和 的耐碳青霉烯 分离株的报告。
