A Survey for Detection of Eight Correlated Genes of Avian Pathogenic Escherichia coli in Human Uropathogenic Escherichia coli

A wide range of extraintestinal infections in humans and vertebrate animals are created by the extraintestinal E. coli strains (EXPEC), including APEC (Avian pathogenic Escherichia coli) and UPEC (urinary tract infection in humans). This study aimed to survey presence of eight involving virulent genes of APEC and UPEC strains in human extraintestinal E.coli strains to support the hypothesis that these genes in human APEC and UPEC were originated from avian APEC and UPEC strains.  

A total of 100 and 105 Escherichia coli samples were collected from patients with urinary tract infection and the infected chickens with colibacillose, respectively. After DNA extraction, Multiplex PCR was used for the presence of genes astA, iss, papC, iucD, tsh, vat, cva / cvi (related to strain APEC). Correlation between APEC and UPEC were analyzed by chi-square test.  

The frequency of astA, iss, irp2 and papC genes in UPEC strains isolated from patients with urinary tract infection were 13%, 11%, 33% and 3%, respectively. The genes iucD, tsh, vat, and cva / cvi were observed in ​​only one of the isolated strains. All genes were observed in all avian strains.

presence of astA, iss, irp2, papC genes in both APEC and UPEC strains confirmed their role in extraintestinal infections. Between them, iss gene (the most common isolated gene) and irp2 gene (with 33% frequency in of UPEC) are more likely the most important pathogenic factors in the E. coli strains.