[The molecular mechanisms of resistance to B-lactams of pathogens of hospital-acquired infections].

The data of local microbiologic monitoring was used to study the profiles and mechanisms of resistance to beta-lactams antibiotics of gram-negative isolates of bacteria, pathogens of hospital-acquired infections in hospital reanimation and surgical departments. The study included 210 clinical isolates of pathogens of hospital-acquired infections: Pseudomonas aeruginosa--86 (40.9%), Acinetobacter baumannii--45 (21.4%), Klebsiella pneumoniae--52 (24.8%), Escherichia coli-23 (11.0%), Enterobacter spp.--4 (1.9%). The profiles of resistance to antibiotics were analyzed using the technique of serial micro-dilutions. The detection of the most common and clinically significant gens of beta-lactamases of gram-negative bacteria was implemented using the PCR technique and sequence analysis. The most activity was detected among carbapenems and cephaperazone/sulbactam. The local characteristics of prevalence of gens coding beta-lactamases (TEM, SHV, CTX) in K. pneumoniae and E. coli were established The study detected 11 isolates of P aeruginosa resistant to carbapenems and having genetic determinants of VIM-group and coding metal-beta-lactamases. The discussed data permits to assess the indicators of resistance to beta-lactams antibiotics and basic mechanisms of resistance of causative agents of hospital-acquired infections. The studies of this kind are unique for every type of hospital-acquired infection. The results can be used in the development of the concept of etiotropic and empiric therapy.