Infection and Drug Resistance (Mar 2022)
Emergence of Carbapenem-Resistant ST244, ST292, and ST2446 Pseudomonas aeruginosa Clones in Burn Patients in Yunnan Province
Abstract
Yue Fang,1,* Zulqarnain Baloch,1,* Wei Zhang,2 Ying Hu,2 Rui Zheng,3 Yuzhu Song,1 Wenlin Tai,2 Xueshan Xia1 1The Affiliated AnNing First Hospital & Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, People’s Republic of China; 2The 2nd Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, 650101, People’s Republic of China; 3The First Hospital of Yunnan Province & The Affiliated Hospital, Kunming University of Science and Technology, Kunming, Yunnan, 650034, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yuzhu Song; Xueshan Xia, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, 650500, People’s Republic of China, Tel +86-871-65920756, Fax +86-871-65920570, Email [email protected]; [email protected]: The prevalence of carbapenem-resistant Pseudomonas aeruginosa is increasing persistently, particularly in burn ward isolates. Here, we investigate the prevalence of carbapenem-resistant Pseudomonas aeruginosa in a burn ward of a provincial-level hospital at Kunming, Yunnan province, China.Methods: A total of 118 P. aeruginosa strains were isolated from 57 hospitalized patients, and their MICs were measured. Carbapenem-resistant isolates were selected for multilocus sequence typing (MLST). Carbapenem-resistance mechanisms were identified by examining carbapenemase genes and OprD protein and Carba-NP testing. Representative isolates were further characterized by de novo sequencing for carbapenemase molecular background.Results: Among 118 P. aeruginosa isolates, 54 (54/118,45.8%) were carbapenem-resistant Pseudomonas aeruginosa, and 3 genotypes were found (ST292, ST244, and ST2446). Non-carbapenemase-producing ST292 was the most prevalent ST, followed by ST2446 and ST244. A novel 13-bp oprD deletion was found in the ST292 clone, which formed the truncated outer membrane protein and may cause carbapenem resistance. ST244 and ST2446 harbored blaIMP-45 and blaIMP-87, respectively. blaIMP-45 is located in a megaplasmid, together with aac(6’)-Ib3, blaOXA-1, catB3, qnrVC6, armA, msr(E), mph(E), aph(3’)-Ia, tetC/tetR, aac(6’)-Ib3, floR, mexC-mexD-oprJ, fosA and lead to extensive drug resistance. ST2446 contains a carbapenem-resistant gene blaIMP-87 on the chromosome and is acquired by a novel gene cassette array (blaIMP-87-ant(2”)-Ia-blaOXA-10-aac(6’)-Ib3) of class 1 integron.Discussion: For the first time, ST244, ST292 and ST2446 are reported emerging in burn patients, with distinctive carbapenem-resistance mechanisms, respectively. The obtained results highlight the need to surveillance carbapenem-resistant isolates in burn patients.Keywords: P. aeruginosa, carbapenem-resistance, oprD, blaIMP
