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 multicentre microbiological survey conducted in four Ukrainian military hospitals between 2014 and 2020. The phenotypes of 813 organisms obtained from 1,061 tests of 162 patients were analysed. Fifty-two isolates underwent whole genome sequencing.

FINDINGS: Resistance was highest in A. baumannii, with 92.5% [(48/52) 95% 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 P. aeruginosa, 42.9% in E. coli [(12/28) 95% CI 24.5-62.8], and 32.8% in K. pneumoniae [(20/34) 95% CI 21.3-46.0]. Multidrug-resistant strains harboured an abundance of antibiotic resistance genes. K. pneumoniae coproduced class A and D β-lactamases, in one case with blaNDM-1 and rmtC 16S rRNA methyltransferase. A. baumannii carried class A and D β-lactamases but not metallo-β-lactamases; in four isolates, carbapenemases were present with the RmtASE gene armA. P. aeruginosa harboured a wide range of class A and D β-lactamases along with metallo-β-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.