Uropathogenic Escherichia coli in Iran: Serogroup distributions, virulence factors and antimicrobial resistance properties

Abstract

BackgroundUrinary tract infections (UTIs) are one of the most common bacterial infections with global expansion. These infections are predominantly caused by uropathogenic Escherichia coli (UPEC).MethodsTotally, 123 strains of Escherichia coli isolated from UTIs patients, using bacterial culture method were subjected to polymerase chain reactions for detection of various O- serogroups, some urovirulence factors, antibiotic resistance genes and resistance to 13 different antibiotics.ResultsAccording to data, the distribution of O1, O2, O6, O7 and O16 serogroups were 2.43%, besides O22, O75 and O83 serogroups were 1.62%. Furthermore, the distribution of O4, O8, O15, O21 and O25 serogroups were 5.69%, 3.25%, 21.13%, 4.06% and 26.01%, respectively. Overall, the fim virulence gene had the highest (86.17%) while the usp virulence gene had the lowest distributions of virulence genes in UPEC strains isolated from UTIs patients. The vat and sen virulence genes were not detected in any UPEC strains. Totally, aadA1 (52.84%), and qnr (46.34%) were the most prevalent antibiotic resistance genes while the distribution of cat1 (15.44%), cmlA (15.44%) and dfrA1 (21.95%) were the least. Resistance to penicillin (100%) and tetracycline (73.98%) had the highest while resistance to nitrofurantoin (5.69%) and trimethoprim (16.26%) had the lowest frequencies.ConclusionsThis study indicated that the UPEC strains which harbored the high numbers of virulence and antibiotic resistance genes had the high ability to cause diseases that are resistant to most antibiotics. In the current situation, it seems that the administration of penicillin and tetracycline for the treatment of UTIs is vain.

Shiga-toxigenic Escherichia coli in ready-to-eat food staffs: Prevalence and distribution of putative virulence factors

“…AEEC strains are described by their ability to occur attachingand-effacing (A/E) lesions in the gastrointestinal tract of humans and animals. [2][3][4][5][6][7][8] STEC bacteria are responsible for severe clinical syndromes like Hemorrhagic Colitis (HC), Hemolytic Uremic Syndrome (HUS), bloody and non-bloody diarrhea and Thrombotic Thrombocytopenic Purpura (TTP). [2][3][4][5][6][7][8] Presence of latent virulence factors including Shiga toxins (stx1 and stx2), intimin (eaeA) and hemolysin (hlyA) in the STEC strains of food products make them dangerous pathogens for human health.…”

“…1 Among all pathogenic agents causing food-borne diseases, Escherichia coli (E. coli) strains had a significant position. [2][3][4][5][6][7][8] E. coli is a Gram-negative, non-sporulating, flagellated, rod-shaped and facultative anaerobic bacterium of the Enterobacteriaceae family. Shiga (vero) toxin (Stx)-producing E. coli (STEC) is a subdivision of a significant pathogenic group of this bacterium named enterohemorrhagic E. coli (EHEC).…”

“…Shiga (vero) toxin (Stx)-producing E. coli (STEC) is a subdivision of a significant pathogenic group of this bacterium named enterohemorrhagic E. coli (EHEC). [2][3][4][5][6][7][8] In the other hand, STEC strains are divided into two separate subtypes of EHEC and Attaching and Effacing E. coli (AEEC). EHEC strains are responsible for high morbidity and mortality.…”

Prevalence of Genes Encoding Outer Membrane Virulence Factors Among Fecal Escherichia coli Isolates

“…26 The virulence genes of UPEC bacteria such as iroN, iucD and irp2 have been previously recorded from Iran. 11,12 However, according to published data, there is no information on the occurrence of these genes in FeEC isolates. The distribution of the ompT gene among the studied isolates was also similar to that in the previously reported data.…”

“…Multiple studies have been done in different parts of Iran in order to investigate the frequency of virulence genes among UPEC. [11][12][13] However, there is no information about the frequency of virulence mediators in FeEC isolated from human in Iran. Therefore, this study was conducted to examine the distribution of 8 virulence factors, including type 1 fimbriae (fimH), iron-regulated gene homologue adhesion (iha), alpha-hemolysin (hlyA), outer membrane protease (ompT), aerobactin (iucD), yersiniabactin (irp2), salmochelin receptor (iroN) and cytotoxic necrotizing factor 1 (cnf1) in E. coli strains isolated from human feces in Zabol, southeast of Iran, by using the multiplex polymerase chain reaction (PCR) method.…”