Whole genome sequencing of <i>Acinetobacter baumannii</i> strains isolated from hospital patients in the northern territories of the Tyumen region

Abstract

Introduction. is to The analysis of the genetic relatedness of isolates aiming to find the source of infection is an important task of nosocomial infection control. The most common causative agent of healthcare-associated infections is Acinetobacter baumannii.Objective. To evaluate the results of whole genome sequencing of A. baumannii bacteria isolated from clinical samples of patients undergoing inpatient treatment in the northern territories of the Tyumen region.Materials and methods. Nine isolates of A. baumannii from the clinical material of patients were studied. Bacterial cultures were identified by mass spectrometry. Whole genome sequencing, multilocus sequence typing and search for markers of antibiotic resistance were performed.Results. The studied strains belonged to sequence types ST2 and ST187, and to the international clonal complex CC2. All A. baumannii isolates were found to have beta-lactamase genes, as well as genes for resistance to aminoglycosides, to the MLS group of antibiotics, and to tetracyclines. The presence of a cluster of genes associated with virulence was detected: those responsible for the synthesis of acinetobactin and iron binding, surface antigen 1 and porin.Conclusion. Based on data of a single nucleotide polymorphism (SNP) analysis, A. baumannii isolates from the clinical material of patients of healthcare institution #1 belong mainly to one bacterial strain. Isolates of A. baumannii from the clinical material of patients of healthcare institution #2 are closely related. The ability to distinguish clinical isolates of A. baumannii at the level of several SNPs per genome will improve the identification of the source of infection, and whole genome sequencing data can contribute to the rational prescription of antibiotic therapy and the correction of disinfection and antiseptic measures.