Genomic Determinants of Pathogenicity and Antimicrobial Resistance of Nosocomial Acinetobacter baumannii Clinical Isolates of Hospitalized Patients (2019–2021) from a Sentinel Hospital in Hangzhou, China

Abstract

Chenxing Wei,1,* Jian Chen,1,* Tanveer Muhammad Anwar,2,* Lingling Huang,1 Wenjie Yang,3 Xueyan Dong,1 Qiong Chen,1 Min Yue,2,4,5 Daojun Yu1,3 1Department of Medical Laboratory, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, People’s Republic of China; 2Department of Veterinary Medicine, Institute of Preventive Veterinary Sciences, Zhejiang University College of Animal Sciences, Hangzhou, 310058, People’s Republic of China; 3Department of Medical Laboratory, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, People’s Republic of China; 4Hainan Institute, Zhejiang University, Sanya, 572025, People’s Republic of China; 5State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, People’s Republic of China*These authors contributed equally to this workCorrespondence: Min Yue; Daojun Yu, Email [email protected]; [email protected]: Acinetobacter baumannii (A. baumannii or AB) is one of the most opportunistic, nosocomial pathogens threatening public healthcare across countries. A. baumannii has become a primary growing concern due to its exceptional ability to acquire antimicrobial resistance (AMR) to multiple antimicrobial agents which is increasingly reported and more prevalent every year. Therefore, there is an urgent need to evaluate the AMR knowledge of A. baumannii for effective clinical treatment of nosocomial infections. This study aimed to investigate the clinical distribution AMR phenotypes and genotypes, and genomic characteristics of A. baumannii isolates recovered from hospitalized patients of different clinical departments of a sentinel hospital to improve clinical practices.Methods: A total of 123 clinical isolates were recovered from hospitalized patients of different clinical departments during 2019– 2021 to analyze AMR patterns, and further subjected to whole-genome sequencing (WGS) investigations. Multi-locus sequence typing (MLST), as well as the presence of antimicrobial-resistant genes (ARGs), virulence factor genes (VFGs) and insertion sequences (ISs) were also investigated from WGS data.Results: The results highlighted that A. baumannii clinical isolates had shown a high AMR rate, particularly from the intensive care unit (ICU), towards routinely used antimicrobials, ie, β-lactams and fluoroquinolones. ST2 was the most prevalent ST in the clinical isolates, it was strongly associated to the resistance of cephalosporins and carbapenems, with blaOXA-23 and blaOXA-66 being the most frequent determinants; moreover, high carrier rate of VFGs was also observed such as all strains containing the ompA, adeF, pgaC, lpsB, and bfmR genes.Conclusion: Acinetobacter baumannii clinical isolates are mostly ST2 with high rates of drug resistance and carrier of virulence factors. Therefore, it requires measurements to control its transmission and infection.Keywords: Acinetobacter baumannii, antimicrobial resistance, genetic determinants, virulence factors, whole-genome sequencing

Keywords

• acinetobacter baumannii
• antimicrobial resistance
• genetic determinants
• virulence factors
• whole-genome sequencing