Molecular Mechanism of Polymyxin Resistance in Multidrug-Resistant Klebsiella pneumoniae and Escherichia coli Isolates from Henan Province, China: A Multicenter Study

Wenjuan Yan,1,* Qi Zhang,1,* Yingjie Zhu,1 Nan Jing,1 Youhua Yuan,1 Yi Zhang,2 Siying Ren,3 Dongmei Hu,4 Wenmin Zhao,5 Xiaojuan Zhang,6 Caiqin Shi,7 Meiyun Wang,8 Yi Li1 1Department of Clinical Microbiology, Henan Provincial People’s Hospital, People’s Hospital of Zhengzhou University, People’s Hospital of Henan University, Zhengzhou, Henan, People’s Republic of China; 2Department of Clinical Laboratory, Zhengzhou Central Hospital, Affiliated to Zhengzhou University, Zhengzhou, Henan, People’s Republic of China; 3Department of Clinical Laboratory, Kaifeng People’s Hospital, Kaifeng, Henan, People’s Republic of China; 4Department of Clinical Laboratory, Zhumadian First People’s Hospital, Zhumadian, People’s Republic of China; 5Department of Clinical Laboratory, Kaifeng Central Hospital, Kaifeng, Henan, People’s Republic of China; 6Department of Clinical Laboratory, Gongyi People’s Hospital, Zhengzhou, Henan, People’s Republic of China; 7Department of Microbiology Laboratory, KingMed Diagnostics, Zhengzhou, Henan, People’s Republic of China; 8Department of Medical Imaging, Henan Provincial People’s Hospital & the People’s Hospital of Zhengzhou University, Zhengzhou, Henan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yi LiDepartment of Clinical Microbiology, Henan Provincial People’s Hospital, People’s Hospital of Zhengzhou University, People’s Hospital of Henan University, Zhengzhou, Henan, People’s Republic of ChinaTel +86 159 39039006Email liyilabmed@henu.edu.cnPurpose: To evaluate polymyxin-resistant Klebsiella pneumoniae and Escherichia coli prevalence and characteristics in the Henan province, China.Materials and Methods: A total of 2301 bacterial isolates collected at six hospitals were assessed. Their response to polymyxin was evaluated by minimum inhibitory concentration (MIC) analysis, and the mobilized colistin resistance (mcr) and carbapenemase g