Gao Fei, Xiong Zhile, Liang Bingshao, Huang Zhenting, Deng Qiulian, Wang Jielin, Zhong Huamin, Long Yan, Zhu Sufei
Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong 510623, China.
Can J Infect Dis Med Microbiol. 2023 Jan 30;2023:4762143. doi: 10.1155/2023/4762143. eCollection 2023.
Carbapenem-resistant (CRE) are spreading worldwide, posing a serious public health concern. However, the data on CRE strains that cause infections in children in Guangzhou remain limited. Therefore, this study aimed to investigate the epidemiology of CRE, drug resistance, and resistance mechanisms in children in Guangzhou, Southern China.
In total, 54 nonrepetitive CRE strains were collected in pediatric patients at three centers in Guangzhou, Southern China, from January 2016 to August 2018. CRE isolates were used for further studies on antimicrobial susceptibility, the modified Hodge test (MHT), the modified carbapenem inactivation method (mCIM), and drug resistance genes. Multilocus sequence typing (MLST) was used to elucidate the molecular epidemiology of .
The isolated CRE strains include 34 (63.0%), 10 (18.5%), 4 (7.4%), and 6 (11.1%) strains. The strains were isolated mainly from the blood (31.5%, = 17), sputum (31.5%, = 17), and urine (16.7%, = 9). All CRE isolates were highly resistant to the third- or fourth-generation cephalosporins, carbapenems, and -lactam + -lactamase inhibitors (94.4%-96.3%). In addition, the resistance rates to amikacin, ciprofloxacin, levofloxacin, tigecycline, and colistin were 5.6%, 14.8%, 16.7%, 9.3%, and 0%, respectively. Carbapenemase was detected in 35 (64.8%) of the CRE isolates. The most dominant carbapenemase gene was ( = 17, 48.6%), followed by ( = 13, 37.1%) and ( = 4, 11.4%). Other carbapenemase genes ( , , , , , , and ) and the -1 gene were not detected. MLST analysis showed high diversity among the , and ST45 (11.7%, 4/34) was the dominant sequence type.
This study revealed was the most dominant carbapenemase gene in children in Guangzhou. Infection control measures need to be taken for the prevention and treatment of CRE infections.
耐碳青霉烯类肠杆菌科细菌（CRE）正在全球范围内传播，引起了严重的公共卫生关注。然而，关于在广州导致儿童感染的CRE菌株的数据仍然有限。因此，本研究旨在调查中国南方广州儿童中CRE的流行病学、耐药性及耐药机制。
2016年1月至2018年8月期间，在中国南方广州的三个中心收集了54株非重复的儿科患者CRE菌株。将CRE分离株用于进一步的抗菌药物敏感性研究、改良Hodge试验（MHT）、改良碳青霉烯灭活方法（mCIM）及耐药基因研究。采用多位点序列分型（MLST）来阐明分子流行病学。
分离出的CRE菌株包括34株（63.0%）、10株（18.5%）、4株（7.4%）和6株（11.1%）。这些菌株主要从血液（31.5%，n = 17）、痰液（31.5%，n = 17）和尿液（16.7%，n = 9）中分离得到。所有CRE分离株对第三代或第四代头孢菌素、碳青霉烯类及β-内酰胺类+β-内酰胺酶抑制剂均高度耐药（94.4%-96.3%）。此外，对阿米卡星、环丙沙星、左氧氟沙星、替加环素和黏菌素的耐药率分别为5.6%、14.8%、16.7%、9.3%和0%。在35株（64.8%）CRE分离株中检测到碳青霉烯酶。最主要的碳青霉烯酶基因是blaNDM（n = 17，48.6%），其次是blaKPC（n = 13，37.1%）和blaIMP（n = 4，11.4%）。未检测到其他碳青霉烯酶基因（blaVIM、blaOXA-23、blaOXA-48、blaOXA-51、blaOXA-181、blaGES和blaSPM）及qnr-1基因。MLST分析显示菌株间具有高度多样性，ST45（11.7%，4/34）是主要的序列型。
本研究表明blaNDM是广州儿童中最主要的碳青霉烯酶基因。需要采取感染控制措施来预防和治疗CRE感染。
