[Formation of Enterobacter cloacae resistance to disinfectants under the effect of bactericidal concentrations of quaternry ammonium compounds in the experiment].

AIM: Study the possibility of formation of induced resistance of purulent-septic infection (PSI) causative agents against disinfectants (DI) in bactericidal concentrations. MATERIALS AND METHODS: Daily exposure to bactericidal concentrations of preparations from the group of quaternary ammonium compounds (QAC) on Enterobacter cloacae strain that has incomplete sensitivity to the same disinfectants on the same test objects was carried out in experiments on test objects from wood and plastic. Exposure was carried out until the moment of transition from incomplete sensitivity to resistance. RESULTS: E. cloacae strain that initially had incomplete sensitivity to various disinfectants of the QAC group in antibacterial concentrations according to manuals acquires resistance on test objects from wood and plastic after 2 - 12 exposures to the preparations. CONCLUSION: The data obtained give evidence that the resistance of PSI causative agents to disinfectants can take place not only under the influence of low concentrations of the preparations but also during use of disinfectants at bactericidal concentrations.

[Sensitivity of nosocomial purulent-septic infection causative agents to disinfection agents and antibiotics].

AIM: Study the sensitivity of nosocomial purulent-septic infection (PSI) causative agents to disinfectants (DA) and antibiotics (AB). MATERIALS AND METHODS: Sensitivity to DA and AB of 209 PSI causative agent strains isolated from patients and the environment of 2 obstetric and 3 surgical hospitals was studied in 2009-2011. Sensitivity to DA of 94 strains and to AB of 189 strains of Pseudomonas aeruginosa isolated from patients with signs of PSI of reanimation and intensive therapy and surgical departments of a multi-field hospital was studied in 2012. Sensitivity to DA was determined on test-surfaces and in solution according to guidelines by V.V. Shkarin et al., 2010; sensitivity to AB - by disc-diffusion method. RESULTS: Among PSI causative agents resistant to DA the portion of poly-antibiotic resistant strains is higher than among microorganisms sensitive to DA, and among antibiotic resistant bacteria the number of strains resistant to DA is higher than among sensitive to antibiotics. The increase of resistance to DA and AB of P. aeruginosa strains is observed in parallel to the increase of volume of the antibacterial preparations used. CONCLUSION: The results obtained give evidence of the possibility of formation of combined (associated) resistance to DA and AB by nosocomial PSI causative agents against the background of increase of their consumption.