Substantiation of overcoming of antibiotic resistance in Acinetobacter baumannii clinical strains by usage of decamethoxinum

Abstract

Introduction. Non-fermenting Gram-negative bacilli are known as one of the most frequent causative agents of hospital-acquired infections. Acinetobacter baumanii, as causative agent of infection complications of different localization, has obtained recently high resistance to antibiotics and has belonged to ESKAPE group of pathogens. Antimicrobials, recommended for the prophylaxis ant therapy of hospital-acquired infections, have been failing in their effectiveness and lead to selection of antibiotic resistant strains of A. baumanii.The aim of this research was to substantiate the way of overcoming of resistance in clinical strains of A. baumannii, by means of synergic antimicrobial activity of antibiotics and antiseptic decamethoxinum^®. Material and methods. The research was carried out on 190 clinical strains of A.baumannii, isolated from patients with burn disease in 2011-2015 years. The sensitivity of clinical strains of A.baumannii was determined to such antibiotics as ampicillin/sulbactam, cefoperazone, cefoperazone/sulbactam, meropenem, imipenem, amikacin, ciprofloxacin, gatifloxacin and antiseptic decamethoxinum^® (DCM; Registration certificate № UA/14444/01/01 since 24.06.2015. Order of Ministry of Health of Ukraine № 373). The sensitivity of A.baumannii to antibiotics and DCM were done by means of disc-diffusion method and serial dilution one (Order of Ministry of Health of Ukraine №167 since 05.04.2007 year; EUCAST Expert rules). The research of the influence of antiseptic DCM on the sensitivity of acinetobacteria to antibiotics was studied on 35 clinical strains of A.baumannii, drafted from the general number of isolates enrolled in the research. For this, the sensitivity of A.baumannii to antibiotics in the presence of subminimal inhibitory concentrations (subMIC) of DCM was identified. The received experimental data were analyzed by «Statistica 6.0». Results and discussion. The changes of antibiotic sensitivity profile of A.baumannii during five years were shown. The sensitivity of A.baumannii to majority of antibiotics, selected for study, was found to decrease significantly. But the only ampicillin/sulbactam was found to have vice versa tendency. We found the rising quantity of antibiotic resistant strains of A.baumannii. At the same time, high resistance of acinetobacteria in 2015 year was found to fluoroquinolones (ciprofloxacin – 96,1%; gatifloxacin – 95,8%). The in vitro research of combined activity of antiseptic remedy DCM and early mentioned antibiotics against clinical strains of A.baumannii demonstrated the reveal antibiotic effectiveness. As follows, minimal inhibitory concentrations of antibiotics decreased in 1,5-4 times in the mediums, had contained subMIC of DCM. Especially vividly this tendency was found in resistant clinical strains. Conclusion. Under selective influence of antibiotic use of protected by inhibitors β-lactams, carbapenems, fluoroquinolones, aminoglycosides the antibioticresistance increases in A.baumannii, causative agents of infectious complications in patients with burn disease. The antiseptic remedy decamethoxinum^® helps to improve antibiotic sensitivity in resistant A.baumannii.