Microbial landscape of wounds in patients with combat trauma of extremities

Objective.

To analyze the profile of bacterial pathogens in patients with extremities wounds resulting from mine-blast injuries, and their susceptibility to antibacterial drugs.

Materials and Methods.

The prospective observational study enrolled 234 patients who suffered injuries to the lower and/or upper extremities in the period from 4 to 36 days (mean 14.9 ± 7.4 days) before admission to the hospital. All study participants were men. The age of study patients ranged from 19 to 59 years (mean 35.8 ± 8.4 years). During the hospital stay, microbiological analysis of wound samples obtained during surgical treatment of wounds was regularly performed. The wound samples were cultured on nutrient media and microorganisms were identified in accordance with standard methods and procedures.

Results.

According to the results of microbiological analysis of wound samples, the growth of microorganisms was detected in 91.5% of patients. Acinetobacter baumannii (44.4%), Enterococcus faecalis (43.9%), Pseudomonas aeruginosa (26.2%) and Klebsiella pneumoniae (17.3%) were most often detected in the initial study. In 22.2% of patients, wounds were infected with one microorganism; in 77.8%, associations of two or more pathogens were found, most often A. baumannii and E. faecalis (36%) and P. aeruginosa and E. faecalis (18%). In total, pan-resistant, extremely resistant and multiresistant among A. baumannii were 40.5, 36.5 and 9.5%, among K. pneumoniae – 42.3, 46.1 and 7.7%, P. aeruginosa – 17.9, 33.3 and 33.3% of isolates. Almost all isolates of E. faecalis (98.9%) were sensitive to the tested antibacterial drugs. The majority (78.2%) of patients were prescribed antibiotics; the most used antibiotics were amikacin (42.1%), vancomycin (33.3%), and cefepime (28.4%). Combined antibacterial therapy was used in 57.2% of cases. The most frequently prescribed combinations of antibiotics were cefepime with sulbactam, vancomycin with amikacin, and meropenem with vancomycin. Along with antibacterial drugs, all patients underwent surgical treatment of wounds and vacuum-assisted therapy. In 67 patients (41.1%) the same microbiota remained in the wounds during hospital treatment. In 96 (58.9%) patients, other pathogens were identified in a series of subsequent microbiological analyses. The most common new pathogens were E. faecalis (28.4%), A. baumannii (24.2%), and K. pneumoniae (18.9%).

Conclusions.

The study results indicate a high incidence of wound infection in patients with combat injuries to the extremities. The most frequently identified bacterial pathogens were A. baumannii, E. faecalis and P. aeruginosa. Among enterobacteria and A. baumannii, pan-resistant and extremely resistant prevailed; most enterococci demonstrated susceptibility to traditionally used antibacterial drugs.