Children’s City Clinical Hospital No. 9, State Scientific Center of Antibiotics, Moscow, Russia
Profiles and mechanisms of resistance to beta-lactam antibiotics of isolates of Gram-negative microorganisms, which are causative agents of infections in Intensive Care Unit of hospital surgery department, were studied. Two hundred and ten clinical isolates were studied: Pseudomonas aeruginosa — 86 strains (40.9%), Acinetobacter baummanii — 45 strains (21.4%), Klebsiella đneumoniae — 52 strains (24.8%), Escherichia coli — 23 strains (11%), Enterobacter spp. — 4 strains (1.9%). Profiles of antibiotic resistance were studied by the method of serial microdilutions; detection of most widespread and clinically significant genes of beta-lactamases of Gram-negative bacteria was performed by polymerase chain reaction. Carbapenems and cefoperazone/sulbactam were the most active antibiotics. Local features of distribution of beta-lactamase coding genes (TEM, SHV, CTX) in K.đneumoniae and E.coli isolates were revealed. Eleven strains of P.aeruginosa resistant to carbapenems and possessing genetic determinants of VIM-group, which codes metallo-beta-lactamases, were isolated. Obtained data allows to assess the parameters of resistance to beta-lactam antibiotics and to reveal the main mechanisms of such resistance in etiologic agents of nosocomial infections, that, in its turn, allows to choose preparations for etiotropic therapy.
Zh. Microbiol. (Moscow), 2007, No. 5, P. 16—20