Sensitivity to antibacterial drugs in agents of community-acquired infections

Abstract

Introduction The widespread and uncontrolled use of antibiotics leads to selection of resistant strains and rise to atypical forms of most infectious agents. Constantly progressive resistance of microorganisms is currently the most important negative phenomenon of antibiotic therapy. The aim of the work was to optimize antibiotic therapy in community-acquired infections. The objective of study was to determine the range and degree of resistance in clinical isolates of microorganisms of different taxonomic groups, obtained from patients in outpatient care.
Material and methods 213 clinical isolates of microorganisms obtained from patients in outpatient care were studied: 34,7 % strains were obtained from patients with inflammatory processes in upper respiratory tract, 11,7 % – with ear inflammation, 36,6 % – with inflammatory diseases of urinary and genital tracts, 11,3 % – with of skin and soft tissues inflammation, 4,2 % – eye inflammation and 1,4 % – with postoperative infectious complications. The collection of clinical material was performed accordingly before the start of antibacterial therapy. Microorganisms’ isolation and identification were carried out with the help of microbiological methods according to the regulatory documents. The study of resistance of bacterial strains to the antibacterial drugs was performed with the help of disc diffusion method on the Muller-Hinton nutritional medium and of fungal strains – on Saburo medium with the use of standard commercial discs.
Results and discussion The array and level of resistance to antibacterial drugs in clinical isolates of microorganisms of different taxonomic groups obtained from patients in outpatient care was established. The research has established that 43,3 % Staphylococcus spp. isolates possessed polyantibiotic resistance and 3,8 % – extensive resistance, only sensitivity to aminoglycosides and glycopeptides was preserved. The majority of beta-haemolytic streptococci was moderately resistant to macrolides (85,7 %), levofloxacine (52,4 %) and chloramphenicole (66,7 %) and resistant to clindamycine (90,5 %). All isolates of E. faecalis demonstrated moderate resistance to II and III generation nitrofurane and chinolone derivatives and a quarter of isolates – to ampycilline. More than a half of clinical isolates of P. aeruginosa (58,3 %) demonstrated polyantibiotic resistance. A quarter of all obtained isolates of P. aeruginosa possessed extensive resistance, preserving sensitivity to only monobactames and carbapenemes. Among Enterobacteriaceae spp. 44,4 % of strains were polyresistant. One strain of E. сoli isolated from genital tract had extensive resistance. The majority of studied С. albicans fungal strains were sensitive to all studied antifungal agents. The percent of strains resistant to antifungal agents was between 8,6 and 17,1 %.  Conclusion In 30,5 % of all studies clinical isolates multiple drug resistance was observed. Polyantibiotic resistance was show in 58,3 % P. aeruginosa isolates, 44,4 % Enterobacteriaceae spp. strains and in 43,3 % studied Staphylococcus spp. isolates. According to the study results, the significant portion of antibiotic resistant and polyresistant strains of Staphylococcus spp., P. aeruginosa and microorganisms of Enterobacteriaceae family circulating in outpatient conditions are probable producers of beta-lactamases.