Center for Disease Control and Prevention of PLA, Beijing, China.
Center for Disease Control and Prevention of PLA, Beijing, China; School and Hospital of Stomatology, Hebei Medical University, China.
J Glob Antimicrob Resist. 2022 Jun;29:88-96. doi: 10.1016/j.jgar.2022.02.008. Epub 2022 Feb 17.
Since the gene encoding mobilised colistin resistance (mcr-1) was first reported in China in 2015, it has been reported in various Enterobacteriaceae worldwide. Escherichia coli, one of the main pathogens causing diarrhoea, is the most prevalent, clinically identified species carrying mcr-1. This study aimed to investigate the epidemiologic and genomic characteristics of mcr-1 in Escherichia coli from patients in Shanghai.
Faecal samples were collected from hospitals in Shanghai between 2012 and 2015. Polymerase chain reaction was performed to detect mcr-1, and molecular characteristics of the mcr-1-positive E. coli was determined by antimicrobial susceptibility testing and whole-genome sequencing.
We detected 40 (3.9%) mcr-1-positive E. coli strains from faecal samples in clinical settings between 2012 and 2015 in Shanghai. Mcr-1 was detected in 4 types of E. coli, including atypical enteropathogenic E. coli (aEPEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), and enteroaggregative E. coli (EAEC). Most strains harbouring mcr-1 were isolated from children aged <7 years. Whole-genome sequencing revealed that nearly half of the strains that carried quinolone resistance- or β-lactam resistance-related genes were multidrug-resistant. IncX4 was the predominant type in mcr-1-positive E. coli in Shanghai, but the other types of mcr-1-harbouring plasmids are highly diverse in genetic context.
These data suggest that mcr-1 is prevalent in E. coli strains, especially those identified in diarrhoeal patients in Shanghai, and strengthening the surveillance of mcr-1 transmission, especially in children, is essential.
自 2015 年中国首次报告携带可移动黏菌素耐药基因（mcr-1）的基因以来，该基因已在世界范围内的各种肠杆菌科中被报道。大肠杆菌是引起腹泻的主要病原体之一，也是携带 mcr-1 的最常见的临床鉴定种。本研究旨在调查上海患者携带 mcr-1 的大肠杆菌的流行病学和基因组特征。
收集 2012 年至 2015 年上海医院的粪便样本。通过聚合酶链反应检测 mcr-1，通过药敏试验和全基因组测序确定 mcr-1 阳性大肠杆菌的分子特征。
我们从 2012 年至 2015 年上海临床环境中的粪便样本中检测到 40 株（3.9%）mcr-1 阳性大肠杆菌。mcr-1 存在于 4 种类型的大肠杆菌中，包括非典型肠致病性大肠杆菌（aEPEC）、肠致病性大肠杆菌（EPEC）、肠毒性大肠杆菌（ETEC）和肠聚集性大肠杆菌（EAEC）。携带 mcr-1 的大多数菌株均分离自<7 岁的儿童。全基因组测序显示，近一半携带喹诺酮类药物或β-内酰胺类药物耐药相关基因的菌株为多重耐药株。IncX4 是上海 mcr-1 阳性大肠杆菌中的主要类型，但其他类型的 mcr-1 携带质粒在遗传背景上具有高度多样性。
这些数据表明 mcr-1 在大肠杆菌菌株中普遍存在，尤其是在上海腹泻患者中，因此加强对 mcr-1 传播的监测，尤其是在儿童中，是至关重要的。
