[Detection of diarrheagenic escherichia coil harboring genomic O island 28 isolated from children diarrhea in Taiyuan].

Objective: To investigate the etiologic value of diarrheagenic E. coil harboring genomic O island 28(OI-28) containing five putative virulence genes (Z0608, Z0609, Z0615, Z0634 and Z0635), which were related to RTX (Repeat in toxin) toxin family isolated from children with diarrheal disease in Taiyuan.

Methods: In the study, 257 fecal samples from children with diarrheal disease collected in Shanxi Children's Hospital. Diarrheagenic E. coli and enteropathogenic bacteria were isolated and identified by conventional bacterial culture and typing specific diarrheagenic E. coli (EPEC, EIEC, ETEC and EHEC) diagnostic serum, while diarrheagenic E. coli harboring genomic 01-28 containing five putative virulence genes (Z0608, Z0609, Z0615, Z0634 and Z0635) were detected by PCR and DNA southern blot hybridization.

Results: 206 strains (80.16%) of enteropathogenic bacteria were detected from 257 children with diarrhea disease, containing 149 strains (57.98%) of diarrheagenic E. coli and 57 strains(22.18%) of other entero-pathogenic bacteria. Among 3 strains (2.01%) of EPEC, 2 strains (1.34%) of ETEC, 2 strains (1.34%) EHEC were detected by typing specific serum, while all of the 142 strains (95.30%) isolated were suspected to be diarrheagenic E. coli. 21 strains (14.09%) of diarrheagenic E. coil harboring genomic O1-28 containing five putative virulence genes (Z0608, Z0609, Z0615, Z0634 and Z0635) were detected by polymerase chain reaction and DNA southen blot hybridization, 8 strains (5.37%) of diarrheagenic E. coli containing only one genomic OI-28 virulence gene, 2 strains (1.34%) of diarrheagenic E. coli containing two genomic OI-28 virulence gene. 21 children with diarrhea diseases caused OI-28-harboring E. coli containing five important putative virulence genes were among 0 to 3 years old (80.95%). These children correlating with OI-28-harboring E. coli did not present special clinical symptoms or signs.

Conclusion: The diarrheagenic E. coil harboring genomic OI-28 was one of the important etiology for children with diarrheal disease in summer season.