Serotypes of Enteropathogenic Escherichia coli Isolated fromChildren Under 5 Years of Age

Background: the purpose of this study was to find out the frequency of different serotypes of enteropathogenic escherichia coli (epec) among healthy/diarrheal cases.methods: a total of 191 strains, 111 from diarrheal and 80 from asymptomatic persons were examined. determination of the epec serogroups was performed by agglutination tests using polyvalent and monovalent o antiserum. pcr-rflp analysis of the flagellin-encoding (flic) gene and agglutination tests using polyvalent and monovalent sera against h antigens (h1 to h 56) according to the instructions of the manufacturer was performed.results: seventeen (8.9%) strains were non-motile and untypable with conventional serotyping method that showed as h-. forty-three flic restriction patterns were found for motile and non-motile serotypes. each motile serotype was characterized by one or two flic specific restriction patterns. o142:h48 (6.8%), o86:h48 (6.3%), o111:h21 (4.7%) and o127:h21 (4.2%) were the most prevalent serotypes, and o55:h12/45, o86:h48, o127:h21, o142:h48, o126:h48 and o126:h19 serotypes were the most frequently agents in diarrheal cases, compared to asymptomatic children (p< 0.05). there were common epec serotypes in diarrheal and asymptomatic children, however some serotypes either found only in diarrheal cases or isolated from asymptomatic persons.conclusion: some serotypes were isolated more frequently from diarrheal cases than asymptomatic persons. the conventional serological method using antisera is the basis for the h typing system in e-coli, but it is impossible to serotype non-motile bacteria. pcr-rflp analysis of flic gene is a practical method in identifying the h variant in motile and non-motile epec serotypes and is useful for epidemiological studies.