Bacteriophage sensitivity of opportunistic microbiota in children with gut dysbiosis

Abstract

Aim.As the activity of bacteriophages is species- and strain-specific, it is necessary to study bacteriophage sensitivity in distinct geographic regions with various disease patterns. Here, we aimed to study the lytic activity of specific commercially available bacteriophages againstKlebsiella spp., Proteus spp., andStaphylococcus aureusisolated from the intestines of children with gut dysbiosis.Materials and Methods.Bacteriophage sensitivity was assessed in 315 opportunistic microorganisms (125Staphylococcus aureusstrains, 120Klebsiella spp.strains, 70Proteus spp.strains) isolated from the intestinal microbiota of 300 children < 4 years of age with gut dysbiosis. Bacteriophage preparations were produced by Microgen (Russian Federation). The lytic activity of bacteriophages was studied by a drip method on a Muller-Hinton medium by calculating the area of bacterial culture lysis.Results.We found low sensitivity ofKlebsiella spp.(37.5% sensitive strains) andProteus spp.(41.4% sensitive strains) to specific bacteriophages, albeit there were considerable differences between distinctKlebsiellaspecies (Klebsiella pneumoniae, 56.7% sensitive strains;Klebsiella oxytoca, 18.3% sensitive strains, p = 0.03) andProteusspecies (Proteus vulgaris, 52.0% strains;Proteus mirabilis, 35.6% strains, p = 0.04). Nevertheless, sensitivity toStaphylococcus aureuswas considerably higher (78.4%). In addition, lytic activity of bacteriophages reduced along with the increasing severity of gut dysbiosis.Conclusion.Klebsiella spp.andProteus spp.isolated from children with dysbiosis have low sensitivity to commercially available bacteriophages. Bacteriophage sensitivity positively correlated with gut dysbiosis.