Comparative analysis of resistance of main etiological agents of chronic osteomyelitis isolated from association and in monoculture

Abstract

Introduction. To date, a significant number of works have been published devoted to the analysis of the sensitivity of the leading causative agents of osteomyelitis to modern drugs, however, in the available literature there are no data on a comparative analysis of the antibiotic resistance of bacteria isolated from the osteomyelitis focus from the association and in monoculture. Purpose of the work: to compare the resistance profiles of the leading causative agents of osteomyelitis, depending on the bacterial composition of the focus of infection.Materials and methods. The study included 216 clinical isolates, of which 114 were isolated as part of two-component associations, 102 – in a monoculture from pathological material in patients with chronic osteomyelitis who were treated in the purulent department of National Medical Scientific Centre of Traumatology and Orthopedics n.a. academician G.E. Ilizarov (Kurgan, Russia) from 2018 to 2020. To analyze the resistance profiles, depending on the type of microorganism, modern drugs used in the clinic for the treatment of osteomyelitis were taken into account.Results and its discussion. Effective drugs against P. aeruginosa strains isolated from the association were polymyxin and meropenem, and in monoculture–polymyxin, piperacillin/tazobactam, tobramycin; in relation to strains of K. pneumoniae isolated from the association, it was imipenem, in monoculture – amikacin. S. aureus strains isolated both from the association and in monoculture were highly susceptible to antibacterial drugs.Conclusion. The analysis of the sensitivity of the leading causative agents of osteomyelitis, isolated in monoculture and from the association, to the antibacterial drugs used in the clinic, showed significant differences in the resistance profiles between the groups: for S. aureus strains, 4 antibiotics tested out of 13, for P. aeruginosa strains – 7 out of 13, for K. pneumoniae strains – 12 out of 16. The tested antibacterial drugs were less active against P. aeruginosa and S. aureus strains isolated from associations. In contrast, the percentage of resistant strains of K. pneumoniae was higher among monocultures.