The aim of the study was to identify the dominant clonal lineages of pathogens causing combat wounds and to determine their antimicrobial resistance determinants for the purpose of optimizing antimicrobial drug administration in wartime.

Materials and methods. Microbiological monitoring of combat wound contents was carried out in patients of three medical hospitals in the central region of Ukraine during 2014–2023. Molecular genetic studies involving whole genome sequencing (WGS) of isolated cultures using Next-Generation Sequencing (NGS), followed by multilocus genotyping of genome sequences and gene identification, were performed at the Walter Reed Army Institute of Research (USA). Antibiotic sensitivity was determined using the disc diffusion method in accordance with the EUCAST recommendations.

Results. The results of bacteriological studies of combat wounds of the limbs and soft tissues of the torso during 2022 and 2023 have shown that A. baumannii (35.7 %), K. pneumoniae (20.7 %), and P. aeruginosa (14.9 %) were the most common organisms cultured. For A. baumannii, 95.6 % of isolates were multidrug-resistant (MDR), and 41.1 % were classified as extensively drug-resistant (XDR). Genome sequencing identified several high-risk international clones, including ST2, ST78 and ST1077, which carried the carbapenemase genes blaOXA-23, blaOXA-72 and the 16S methyltransferase gene armA. Among the various strains of P. aeruginosa, isolates of globally distributed clonal lines ST235, ST357, ST773, and ST1047 have been identified.

The K. pneumoniae isolates belonged to five distinct clonal groups: ST395, ST307, ST147, ST39, and ST23. Most of these isolates carried carbapenemases and were classified as MDR and XDR.

Conclusions. This study analyzed bacterial pathogens from combat wounds in Ukraine (2014–2023), revealing a dominance of MDR/XDR Gram-negative organisms, primarily Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae. Whole-genome sequencing identified the emergence of high-risk international clones (e. g. A. baumannii ST2, ST78, ST1077; P. aeruginosa ST235, ST357, ST773, ST1047; K. pneumoniae ST147, ST307, ST395), many carrying blaOXA, blaNDM, 16S rRNA methyltransferases and, in K. pneumoniae, hypervirulence markers. The findings underscore the close association between armed conflict and the amplification of antimicrobial resistance, driven by high antibiotic consumption, complex evacuation pathways, and nosocomial transmission in overstretched healthcare systems.