Molecular study on diarrheagenic Escherichia coli pathotypes isolated from under 5 years old children in southeast of Iran

Objective: To determine the phylogenetic groups and prevalence of diarrheagenic Escherichia coli (E. coli) (DEC) genes from children less than five years of age with diarrhea in southeast of Iran. Methods: A total of 142 E. coli isolates were isolated from diarrheic samples. The isolates were examined for detection of virulence determinants and their phylogenetic background by PCR technique. Results: The E. coli isolates fall into four phylogenetic groups: A (40.14%), B1 (18.31%), B2 (16.90%) and D (24.65%). Eighty isolates were positive for at least one of the examined DEC genes. E. coli isolates were classified in enterotoxigenic E. coli (52 isolates), enteroaggregative E. coli (23), atypical enteropathogenic E. coli (9), enteroinvasive E. coli (2). Conclusions: This study demonstrated the importance of enterotoxigenic E. coli and enteroaggregative E. coli pathotypes in the childhood diarrhea. An epidemiologic surveillance especially for DEC, would be useful in control and prevention of infectious diarrhea in children