Monitoring of the leading causative agents of osteomyelitis and their antibiotic resistance

Abstract

The annual monitoring of the species composition of the causative agents of osteomyelitis, the identification of antibiotic-resistant strains, the study of the species composition of associations of microorganisms, their adhesive activity will prevent the spread of infection. Analyze the spectrum of the leading causative agents of osteomyelitis, their antibiotic sensitivity, and also the adhesive activity of the identified bacterial associations. A microbiological analysis of 2197 smears of adult patients with various etiological forms of osteomyelitis who were treated in the departments of the purulent center of the FSBI «NMRCTO» of the RF Ministry of Health in 2019. The spectrum of pathogenic microflora, sensitivity to standard antibacterial drugs used in the clinic was studied. The biofilm-forming ability of associations of microorganisms was investigated. According to the conducted microbiological monitoring for 2019, the microflora spectrum for osteomyelitis is diverse, the main pathogens are S. aureus, S. epidermidis, P. aeruginosa, K. pneumoniae, Enterococcus sp. A high percentage of isolation of microbial associations was noted, most often mix cultures of gram-positive and gram-negative bacteria. Bacterial associations: S. aureus + P. aeruginosa, S. aureus + S. marcescens, S. aureus + A. baumannii, S. epidermidis + E. cloacae - actively formed a biofilm on the surface of polystyrene plates, and the adhesive potential depended on interstrain relations in the composition of the formed biofilm. Among Gram-negative microflora, multiresistant strains prevail, among Gram-positive microflora - a high percentage of methicillin-resistant Staphylococci. When analyzing the antibiotic sensitivity of the isolated microorganisms, a high percentage of resistant strains is noted. So, with respect to enterobacteria, β-lactam antibiotics, drugs from the group of aminoglycosides, turned out to be ineffective. Among non-fermenting gram-negative bacteria, A. baumannii strains had multiple antimicrobial resistance. Among gram-positive microorganisms, a high percentage of isolation of methicillin-resistant staphylococci was noted. The specificity of the course of the disease and measures aimed at eliminating the pathogen depend on the species composition in the focus of infection. The study of the etiological structure of osteomyelitis, the monitoring of the antibiotic resistance of pathogens and their persistent potential, makes it possible to adopt sound tactics of conservative and surgical treatment.