The Frequency of Stx1 and Stx2 Genes in Uropathogenic Escherichia coli Isolated From Patients in Kermanshah, Iran

Document Type : Original Article


1 Pathobiology & Basic Science Department, Veterinary Faculty, Razi University, Kermanshah, Iran

2 Islamic Azad University, Broujerd, Iran


1) Background: Uropathogenic E. coli (UPEC) is responsible for 70-90% of urinary tract
infections. On the other hand, E. coli producing Shiga toxin (STEC), the so-called Verotoxinproducing E. coli (VTEC), has two stx1 and stx2 genes (Producing Stx1 and Stx2 toxins). Since these genes are plasmidal and can be transmitted between E. coli strains, it is likely that stx1 and stx2 genes are also found in the Uropathogenic E. coli. Studies in different parts of the world indicate some cases of dangerous syndromes such as Haemolytic-Uraemic Syndrome (HUS)following urinary tract infections. Also, the incidence of urinary tract infections caused by Verotoxigenic E. coli strains is increasing. Therefore, the present study was conducted to investigate the presence of verotoxin genes in Uropathogenic E. coli; 2)Methods: A total of 180 clinical specimens were collected during five months. After diagnostic tests and differential biochemistry tests, 100 samples were confirmed as E. coli and the presence of stx2 and stx1 genes was investigated by Muliplex-PCR; 3) Results: The results showed that the prevalence rates of stx1 and stx2 genes were 15% and 13%, respectively, in UPEC samples examined in this study, which is in agreement with the results of few similar studies in Iran; and 4) Conclusions: It seems that the frequency of verotoxin genes in E. coli causing urinary tract infections in Kermanshah is more than the other parts of Iran. Therefore, the potential risks of these bacteria could not be ignored.


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