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Klebsiellapneumoniae is a significant pathogen associated with hospital infections. Its was isolated in intensive care units (ICU) at two pediatric hospitals in Moscow in 2012-2014 from 41% (387/935) of the patients. The rate of carbapenem-nonsusceptibility (Carba-NS) amounted to 25% for imipenem and 27% for meropenem. For further analyses, 67 isolates were selected, including 57 Carba-NS and 10 Carba-susceptible (Carba-S). Among the isolates, 100% was nonsusceptible to the III-IV generation cephalosporins, 50-84% was resistant to aminoglycosides. The rate of nonsusceptibility to ciprofloxacin and phosphomycin exceeded 90%. All the tested Carba-S Kpneumoniae isolates were susceptible to tigecycline, whereas 25% of the Carba-NS isolates was tigecycline-NS. The prevalence of the colistin-NS isolates was the same in Carba-S (20%) and Carba-NS (26%) bacteria. The blamrx_ gene was carried by 100% of the Carba-S isolates, combining with the blaTEM gene in 60% of the isolates. In 89% of the Carba-NS isolates the OXA-48 carbapenemase was detected, which was combined with CTX-M and/or TEM in all but 1 isolate. Thus, over the last decade, the rate of Carba-NS among nosocomial Kpneuynoniae increased and the OXA-48 carbapenemase was shown to be dominating in the mechanism of Carba-NS in the pediatric ICUs in Moscow.

Aim: Characterize spectrum of antibiotics resistance of Acinetobacter baumannii strains, isolated from patients of 8 surgical and reanimation departments of 3 medical institution of Moscow, and determine molecular-genetic mechanisms of stability of their carbapenem-resistant forms., Materials and Methods: 95 strains of A. baumannii, isolated from patients of reanimation and surgical departments of Moscow in 2012-2014, were studied. Sensitivity of strains to antibiotics was tested phenotypically according to recommendations of EUCAST. The presence of VIM, IMP, OXA-23, OXA-40, OXA-48, OXA-58 and NDM genes in the studied strains was determined by polymerase chain reaction in real time., Results: 86.3% of strains turnedout to be non-sensitive to carbapenems, sensitive--13.7%. 80.0% of strains were non-sensitive to gentamicin, 80.0% of strains--to netilmicin, 94.7% of strains--to ciprofloxacin 2.1%--to colistin. 91.6% of isolates have shown non-sensitivity to members of 2 and more classes of antibiotics, 78.9% of strains--to members of 3 classes. 2 strains were panresistant, 4.2% (4/95) of the isolates were sensitive to all the classes of antibiotics. Metallo-β-lactamases were not detected. Genes of carbapenemases (OXA-23 and/or OXA-40) were detected in 85.3% (81/95) of strains, characterized phenotypically as non-sensitive to carbapenems., Conclusion: The results obtained shown an increase of resistance to carbapenems and multiple resistance in clinically significant strains of A. baumannii. Resistance to carbapenems is associated with OXA-23 and OXA-40 genes. The conclusions allow to justify perspectives of introduction of technologies of molecular-genetic testing of antibiotics resistance.

Nosocomial infections and their rational antibiotic treatment represent a major challenge for the healthcare nowadays. In this context, gramnegative bacteria including Pseudomonas aeruginosa, Acinetobacter baumanii and Enterobacteriaceae spp. are etiologically important and characterized by a significant level of antibiotic resistance. To examine dynamics of the respiratory tract colonization by hospital flora, tracheal aspirates obtained at three time points from 69 children with severe craniocerebral trauma during their stay in ICU were analysed. Colonization was observed on the 4th day of the ICU stay with predomination of K. pneumoniae (45%) and A. baumanii (27-37%). P. aeruginosa was detected after the 8th day of the ICU stay with the isolation rate of 33%. Substantial proportions of P. aeruginosa (61%), A. baumanii (78%) and K. pneumoniae (25%) were resistant to carbapenems. In 65 carbapemen resistant isolates, the presence of carbapenemases was examined using PCRs. OXA-48 carbapenemase was detected in 11 out of 14 (78%) K. pneumoniae isolates. Among the A. baumanii isolates, 30/31 (97%) carried OXA-40 and 1/31 (3%) had OXA-23 carbapenemases. None of the examined A. baumanii and K. pneumoniae isolates produced metallo-betalactamases (MBL). In contrast, all 20 carbapenem resistant P. aeruginosa isolates produced a MBL, and in 12 out of 20 (60%) of theme VIM-2 was detected. Thus, gramnegative nosocomial microflora rapidly colonizes ICU patients and has a high level of resistance to antibiotics, including carbapenems.