THE IDENTIFICATION OF GENES FOR THE PATHOGENICITY OF ESCHERICHIA COLI FOR CHRONIC GASTRODUODENITIS AND COMORBID DISEASES ACCOMPANIED BY DYSBIOSIS IN CHILDREN

Abstract

The purpose of the study to reveal diarrheagenic E.coli in routine intestinal dysbiosis diagnostics in children are under regular medical check-up because of chronic conditions. Material & methods: For the purpose of bacteriological diagnostics of intestinal dysbiosis 9–17 years old children were examined with standard procedure. Children were subdivided into groups: 1) children with chronic gastroduodenitis — (22 patients); 2) children with atopic dermatitis (AtD) (19 patients); 3) children with bronchial asthma (7 patients). E. coli strains with typical properties, which isolated from feces of children in the intestinal dysbiosis diagnostics, were examined. Serotyping of E. coli strains was done with agglutinating sera (Ecolab, Russia). In the second stage, isolated strains from all patients were investigated by PCR. Results. In intestinal microbiota of children with chronic gastroduodenitis the changes were significant more specifically increase of staphylococci and other conditionally pathogenic microorganisms including hemolytic bacteria. In the standard bacteriological dysbiosis diagnostics 48 strains of E. coli strains were isolated in different groups of children who was under regular medical check-up. On the first stage of investigation serotyping of typical colonies of E. coli was done. For advanced study using real-time PCR isolated strains were examined. These strains were typified as DAEC (2 strain), EAEC (2 isolates), EPEC and ATEC (2 strains). 1 strain was typified as EHEC. Diarrheagenic E. coli with confirmed virulence coding genes were isolated in children with chronic gastroduodenitis (7 isolates) and in children AtD (4 isolates). These results confirm the need for PCR diagnosis for an adequate assessment of clinical conditions accompanied by dysbiosis.