Profile characteristics of sensitivity to antimicrobial chemotherapeutic drugs of Corynebacterium jeikeium isolated in explosive mine injuries of the limbs

Abstract

Background. From the moment of gunshot wounds, the microbiological landscape depends on the provision of medical care at each evacuation link. Effective antibacterial therapy relies on choosing the right antibiotics based on the pathogen’s sensitivity to them. This approach aims to prevent infectious complications of combat trauma, and it requires continuous microbiological monitoring of circulating microbial strains. Purpose – to study the profile of microorganisms isolated from mine-explosive injuries of the limbs of patients who were admitted to the last stage of medical care in the regional centre of the city of Lviv. To determine the antibiotic susceptibility of the isolated nosocomial pathogen C. jeikeium to antimicrobial chemotherapeutic agents. Materials and Methods. The strains of microorganisms isolated from gunshot wounds of the limbs of 20 male casualties, aged 20 to 50 years upon admission to the Lviv Regional Medical Facility in 2024, were investigated. The collection of material was carried out using sterile swabs in a transport nutrient medium. The material was inoculated onto blood agar, Endo medium, CHROMID® P. aeruginosa Agar, MPA, and incubated at 37°C for 24 hours. Biochemical identification was carried out using the Enterotest 24 and Nefermtest (Lachema, Czech Republic). The cultivation of C.jeikeium was carried out on sheep blood agar, with the purpose of accelerating growth, Tween 80 was used. It was identified based on morpho-tinctorial and cultural properties, and its biochemical activity was studied through the fermentation of glucose and galactose. Considering the fact that the predominant contaminants of combat wounds were 8 strains of C.jeikeium, the sensitivity of these isolates to antimicrobial chemotherapeutic agents was determined using the disc diffusion method with standard discs EUCAST. The sensitivity of the above-mentioned isolates was determined using the disc diffusion method with the use of standard discs. At evaluation of resistance profiles was guided by the EUCAST standard. Results. As a result of the operation, 24 pure cultures were isolated and identified to the species level. The sensitivity of selected isolates of C.jeikeium to vancomycin and linezolid was set at 100%. Sensitivity to tetracycline was 25%, gentamicin and clindamycin – 12.5% each. Given that the sensitivity of 8 isolates of C.jeikeium turned out to be similar; that the majority of cases of infection with this microorganism have a pronounced hospital character, we assume that we have isolated a nosocomial pathogen. Conclusions. Summarizing the results of the study and comparing with the data of other authors, regarding the monitoring of the microbiological landscape of wounds of the limbs, we state that in our study the frequency of detection of P.aeruginosa was – 8.3%, K.pneumoniae – 20.8%, not a single case of isolation of A.baumanii. The most frequently isolated microorganisms were: C.jeikeium – 8 strains (33.3%) with similar sensitivity to antimicrobial chemotherapeutic drugs, which may indicate the isolation of a nosocomial pathogen. The drugs of choice for C.jeikeium elimination are vancomycin and linezolid. After obtaining the result of sensitivity to antibiotics, it is possible to prescribe tetracy cline, gentamicin, clindamycin.