RETRACTED ARTICLE: Shiga Toxigenic Escherichia coli in Iranian Pediatric Patients With and Without Diarrhea: O-Serogroups, Virulence Factors and Antimicrobial Resistance Properties

Abstract

Background:Shiga-toxigenic Escherichia coli is an important human pathogen cause of diarrhea, hemorrhagic colitis, hemolytic uremic syndrome and thrombotic thrombocytopenic purpura in humans is a significant public health.Objectives:The aim of this study was to determine the molecular characteristics and antimicrobial resistance properties of Shiga toxigenic Escherichia coli (STEC) strains with respect to their seasonal, age and geographical distributions in Iranian pediatric patients with and without diarrhea.Patients and Methods:Four hundred and eighty swab samples were taken from pediatric patients with and without diarrhea of four major provinces of Iran. Swab samples were immediately cultured and the positive culture samples were analyzed by the polymerase chain reaction (PCR) method. Finally, antimicrobial susceptibility testing was performed using the disk diffusion method in Mueller-Hinton agar.Results:In total, 118 out of 200 diarrheic stool samples (59%) and 77 out of 280 non-diarrheic stool samples (27.5%) were positive for E. coli. Samples taken from one to ten months old cases (73.33%) and those from Shiraz province (81.13%) were the most commonly infected. Samples taken in the summer season (91.66%) were the most commonly infected. A significant difference was shown between AEEC and EHEC strains of E. coli. The genes encoding Shiga toxins and intimin protein were the most commonly detected in all strains. O26 (33.33%), O111 (18.18%) and O91 (12.12%) serogroups had the highest incidence in patients with and without diarrhea. Prevalence of the genes that encode resistance against ampicillin (CITM), gentamicin (aac(3)-IV) and tetracycline (tetA) were 80.30%, 75.75% and 65.15%, respectively. The STEC strains harbored the highest levels of resistance against ampicillin (84.84%), gentamycin (78.78%), tetracycline (50%) and sulfamethoxazole (40.90%) antibiotics. We found that 55.08% of diarrheic and 1.29% of non-diarrheic E. coli isolates were resistant to more than six antibiotics.Conclusions:Accurate control programs should be organized for antibiotic prescription especially during warmer seasons in Iran. Primary treatment of diarrheic patients with co-trimoxazole, cefotaxime and ceftriaxone is effective.

Shiga (vero) toxin producing Escherichia coli in various types of food stuffs; virulence factors, O‐serogroups and antimicrobial resistance properties

“…Consumption of these foods which harbored the E. coli strains positive in their virulence factors can surely cause severe foodborne diseases. Simultaneous presence of these virulence factors in the E. coli strains of food samples were also reported previously (Bosilevac & Koohmaraie, ; Dormanesh et al, ; Hemmatinezhad et al, ; Madic et al, ).…”

“…A protein called intimin, that was encoded by eae gene and enterohemolysin ( ehly ), or enterohemorrhagic E. coli hemolysin (EHEC‐ hly ) are two other important virulence factors (Schmidt, Beutin, & Karch, ). These genes are responsible for adhesion, colonization and invasion of STEC strains into the intestinal epithelial cells (Dormanesh, Siroosbakhat, Goudarzi, & Afsharkhas, ; Farshad et al, ; Momtaz, Dehkordi, Hosseini, Sarshar, & Heidari, ; Momtaz, Dehkordi, Rahimi, et al, 2013). High prevalence of these genes in the cases of clinical diseases such as HUS, HC and diarrhea had also been reported previously (Dormanesh et al, ; Etcheverria and Padola, ; Melton‐Celsa et al, ; Momtaz, Dehkordi, et al, 2013).…”

“…These genes are responsible for adhesion, colonization and invasion of STEC strains into the intestinal epithelial cells (Dormanesh, Siroosbakhat, Goudarzi, & Afsharkhas, ; Farshad et al, ; Momtaz, Dehkordi, Hosseini, Sarshar, & Heidari, ; Momtaz, Dehkordi, Rahimi, et al, 2013). High prevalence of these genes in the cases of clinical diseases such as HUS, HC and diarrhea had also been reported previously (Dormanesh et al, ; Etcheverria and Padola, ; Melton‐Celsa et al, ; Momtaz, Dehkordi, et al, 2013). The most commonly detected O‐serogroups in the diseases caused by the STEC strains are O26, O45, O91, O103, O111, O113, O121, O128, O145 and O157 serogroups (Jenkins et al, ; Madic et al, ).…”

Virulence Genes and Phenotypic Evaluation of the Antibiotic Resistance of Vero Toxin Producing Escherichia coli Recovered From Milk, Meat, and Vegetables

“…Concurrent attendance of different virulence genes in E. coli strains specified a significant public health issue. Concurrent occurrence of Shiga toxins and intimin has been described before (22)(23)(24)(25)(26). In a survey accompanied by Momtaz et al (2012), the incidence of AEEC and EHEC clusters was 49.31% and 15.06%, respectively (21).…”

“…In a survey accompanied by Momtaz et al (2012), the incidence of AEEC and EHEC clusters was 49.31% and 15.06%, respectively (21). Higher frequency of AEEC subtypes was described by numerous surveys (22)(23)(24)(25)(26). STEC bacteria exhibited severe prevalence of resistance to tetracycline, ampicillin, gentamycin, and ciprofloxacin.…”