[Prevalence of cytotoxicity effectors in nosocomial Pseudomonas Aeruginosa strains].

AIM: Analysis of occurrence of the third type secretory system (TTSS) effectors in clinical P. aeruginosa strains.

MATERIALS AND METHODS: Intra-hospital (n = 164) and extra-hospital (n = 30) strains of P. aeruginosa were studied. Detection of exoS and exoU genes was carried out by PCR in DNA Engine Dyad Thermal Cycler ("Bio-Rad", USA). Metallo-beta-lactamase (MBL) producers were detected by the presence of blaVIM-2 gene.

RESULTS: Screening of intra- and extra-hospital strains for the presence of genes coding ExoS and ExoU showed, that exoS is detected in genome of clinical isolates in 59.8% and exoU--31.1% of cases. At the same time, strains with exoS-/exoU+ genotype predominated in lCU (Φ = 0.466; p = 0.0000). A significant association between the presence of the respective effectors and material of strain isolation was not detected. exoU gene was more frequently detected in genome of MBL producers (Φ = 0.784; p = 0.0004).

CONCLUSION: A significant association between exoU and blaVIM-2 could be explained by clonal prevalence of P. aeruginosa ST235 VIM-2, circulation of those is noted on all the territory of Russia. As a rule, ExoU is produced by highly virulent poly-antibiotic resistant hospital isolates that determine unfavorable outcomes of pseudomonas infection.