Published online by Cambridge University Press: 15 May 2009
Stool specimens from 631 children with acute diarrhoea and from 277 healthy controls were tested for the presence of non-enteropathogenic, non-enterotoxigenic Escherichia coli strains which mediated mannose-resistant haemagglutination of human erythrocytes (MRHA + ). Fifty-nine (34·9%) of 169 isolated MRHA + strains but none of 210 MRHA - strains exhibited diffuse adherence (DA+) to HEp–2 cells. DA+ strains were found in 37 (5·9%) children with diarrhoea and in 22 (7·9%) controls. MRHA + /DA + strains in comparison to MRHA + /DA - strains significantly less frequently expressed P fimbriae (10·7 vs. 73·6%), haemolysin production (12·5 vs. 63·2%), and MRHA of other species erythrocytes (21·4 vs. 84%).
These data demonstrate that E. coli which exhibit the diffuse pattern of adherence to HEp–2 cells also cause MRHA of human erythrocytes. Since these strains were found with similar frequencies in children with and without diarrhoea it seems that DA is not a marker of enteropathogenicity of E. coli.