Phenotypic and genotypic characterization of antibiotic resistance in military hospital-associated bacteria from war injuries in the Eastern Ukraine conflict between 2014 and 2020

Background: Infections from the recent conflict in Ukraine have been poorly investigated. Aim: To describe the phenotypic and genotypic mechanisms of antibiotic resistance in pathogens associated with war injuries in the Ukraine conflict. Methods: This report describes a retrospective multi-centre microbiological survey conducted in four Ukrainian military hospitals between 2014 and 2020. The phenotypes of 813 organisms obtained from 1061 tests of 162 patients were analysed. Fifty-two isolates underwent whole-genome sequencing. Findings: Resistance was highest in Acinetobacter baumannii, with 92.5% ((48/52) 95% confidence interval (CI) 81.8-97.9) resistant to fluoroquinolones, 83.0% ((43/52) 95% CI 70.2-91.9) resistant to aminoglycosides, and 67.9% ((37/52) 95% CI 53.7-80.1) resistant to carbapenems. In contrast, resistance to carbapenems was 55.6% ((30/52) 95% CI 41.4-69.1) in Pseudomonas aeruginosa, 42.9% in Escherichia coli ((12/28) 95% CI 24.5-62.8), and 32.8% in Klebsiella pneumoniae ((20/34) 95% CI 21.3-46.0). Multi-drug-resistant strains harboured an abundance of antibiotic resistance genes. K. pneumoniae co-produced class A and D beta-lactamases, in one case with blaNDM-1 and rmtC 16S rRNA methyltransferase. A. baumannii carried class A and D beta-lactamases but not metallo-beta-lactamases; in four isolates, carbapenemases were present with the RmtASE gene armA. P. aeruginosa harboured a wide range of class A and D beta-lactamases along with metallo-beta lactamases, as well as the RmtB4 RmtASE gene. Gram-positive cocci were generally sensitive to the tested antibiotics. Conclusion: The incidence of resistance among the studied pathogens was higher than that in Ukrainian civilian hospitals and European countries. The discovery of P. aeruginosa, A. baumannii, and K. pneumoniae co-producing carbapenemases and RmtASEs is of particular importance, and hospitals should be vigilant for their emergence. (C) 2021 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study investigated the antibiotic resistance of pathogens associated with war injuries in the Ukraine conflict, revealing high levels of resistance in Acinetobacter baumannii. Multi-drug-resistant strains carried an abundance of antibiotic resistance genes, with some strains co-producing carbapenemases and RmtASEs.