Colistin resistance in clinical Enterobacteriaceae isolates from the Western Cape of South Africa

Colistin resistant E. coli and Klebsiella spp. isolates were collected from the microbiology laboratory at Tygerberg Hospital during 2016 and 2017. Strains were mostly unrelated in 2016 based on rep-PCR, however the majority of the 2017 E. coli isolates were related based on rep-PCR, MLST and SNP analyses. mcr-1 was responsible for >50% of colistin resistance, but mutations in pmrB and disruption of mgrB were common in E. coli and Klebsiella spp. respectively.

2016年与2017年间，从泰格伯格医院（Tygerberg Hospital）微生物实验室收集了粘菌素（Colistin）耐药大肠杆菌（Escherichia coli，简称E. coli）与克雷伯菌属（Klebsiella spp.）分离株。2016年的菌株经重复序列聚合酶链反应（rep-PCR）分析后大多无亲缘相关性；而2017年的多数大肠杆菌分离株经rep-PCR、多位点序列分型（MLST）与单核苷酸多态性（SNP）分析后被证实存在亲缘关联。超过50%的粘菌素耐药性由mcr-1基因介导，但pmrB基因突变与mgrB基因功能失活分别常见于大肠杆菌和克雷伯菌属菌株中。