Spreading and mechanisms of antibiotic resistance of microorganisms, producing beta-lactamases. Molecular mechanisms of resistance to beta-lactams of klebsiella spp. strains, isolated in cases of nosocomial infections
Abstract: Antibiotic sensivity of nosocomial Klebsiella spp. strains (n = 212), isolated from patients treated in 30 medical centers of 15 various regions of Russia was investigated. The Klebsiella genus was represented by the following species: Klebsiella pneumoniae ss. pneumoniae - 182 (85.8%), Klebsiella pneumoniae ss. ozaenae - 1 (0.5%), Klebsiella oxytoca - 29 (13.7%) isolates. The most active antibacterial agents against the investigated strains were carbapenems (imipenem and meropenem). Among 3rd generation cephalosporine the lowest MICs were observed for ceftazidime/clavulanic acid (MIC50 - 0.25 μg/ml, MIC90 - 64 μg/ml) and cefoperazone/sulbactam (MIC50 - 16 μg/ml, MIC90 - 64 μg/ml). Beta-lactamase genes (TEM, SHV, CTX) were detected in 42 Klebsiella pneumoniae ss. pneumoniae strains by PCR. Alone or in various combinations TEM type beta-lactamases have been found in 16 (38.1%) isolates, SHV - in 29 (69%), and CTX - in 27 (64.3%). Combinations of 2 different determinants were detected in 23,8% of the isolates, 3 - in 26,2%. There were not isolates producing MBL class B among resistant to carbapenems nosocomial Klebsiella spp. strains.
Reference: Ivanov D.V., Egorov A.M., Spreading and mechanisms of antibiotic resistance of microorganisms, producing beta-lactamases. Molecular mechanisms of resistance to beta-lactams of klebsiella spp. strains, isolated in cases of nosocomial infections, Biomeditsinskaya khimiya, 2008, vol:
2. Hierholzer W.J., Zernos M.J. (1991) in: Bacterial infections of humans: epidemiology and control (Evans A.S., Brachman P.S., eds.) 2nd edn. Plenum Medical Book Company, New York, pp. 467-497. Scholar google search
3. Сидоренко С.В., Страчунский Л.С., Ахмедова Л.И. и др. (1999) Антибиотики и химиотерапия, 44(11), 7-16. Scholar google search