Virulence properties of Escherichia coli faecal strains isolated in Poland from healthy children and strains belonging to serogroups O18, O26, O44, O86, O126 and O127 isolated from children with diarrhoea.
Four hundred and twenty-seven Escherichia coli isolates from 427 cases of infantile diarrhoea in Poland, belonging to serogroups O18, O26, O44, O86, O126 and O127 and 150 E. coli isolates from 52 healthy children were examined for selected virulence properties. The presence of the plasmid pAA, a plasmid encoding enterohaemolysin, the genes encoding intimin (eae), bundle-forming pili (bfp), Shiga toxins I and II (stxI, stxII) and cytotoxic necrotising factor types 1 and 2 (cnfl, cnf2) was investigated by PCR. Adhesion to HEp-2 cell monolayers was also tested and selected strains were investigated for the presence of P-fimbriae and haemolytic activity. Typical enteropathogenic E. coli isolates (typical EPEC, strains possessing eae and bfp, but not stx) were not found. The particular classes of E. coli among 427 isolates from ill children were: atypical EPEC (eae+ bfp, stx-), 21.3%; Shiga toxin-producing E. coli (STEC), 0.7%; diffusely adherent E. coli (DAEC), 4%; enteroaggregative E. coli (EAEC), 16.9%; necrotoxic E. coli type 1 (NTEC1), 0.2%; and cell-detaching E. coli (CDEC), 29%. With the exception of STEC, all the above classes of E. coli were found among the isolates from healthy children which comprised: atypical EPEC 8.0%, DAEC 6.7%, EAEC 17.3%, NTEC1 14.0% and CDEC 40.0%. Cell detachment (CD) was significantly associated with 3-h haemolytic activity. There was also strong correlation between haemolytic activity (Hly) and the presence of P-fimbriae. No correlation was found between the presence of the cnf1 gene and CD, Hly or P-fimbriae.
Department of Bacteriology, National Institute of Hygiene, 24 Chocimska Street, 00-791 Warsaw, Poland.
Jaroslaw
J
Paciorek
D018829:Adhesins, Bacterial / Q000235:genetics; D000818:Animals; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002460:Cell Line; D002675:Child, Preschool; D003968:Diarrhea, Infantile / Q000382:microbiology*; D004768:Enterotoxins / Q000235:genetics; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D004927:Escherichia coli Infections / Q000382:microbiology*; D029968:Escherichia coli Proteins; D005243:Feces / Q000382:microbiology; D005260:Female; D010861:Fimbriae, Bacterial; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D010641:Phenotype; D010957:Plasmids; D011044:Poland; D016133:Polymerase Chain Reaction; D012703:Serotyping; D022603:Shiga Toxins / Q000235:genetics; D014774:Virulence / Q000235:genetics
D018829:Adhesins, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D002352:Carrier Proteins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D022603:Shiga Toxins; C073819:eaeA protein, E coli