Background: Global increase in the prevalence of virulent extended-spectrum betalactamase (ESBL)-producing uropathogenic Escherichia coli (UPEC), which is also multidrug resistant (MDR), leads to increase in severity of urinary tract infections (UTIs), decrease in the efficacy of the first-line antibiotics, and therefore increase in the morbidity and mortality rates. Methods: We investigated the distribution of ESBL-producing UPEC in 78 E. coli isolates from community-acquired UTI patients in southern Iran. The prevalence of three major ESBL genes, antimicrobial resistance patterns against 15 conventional antibiotic disks, and the presence of 11 important virulence genes that involve in the development and progression of UTIs were evaluated in these isolates. Results: Of the UPECs, 34.6% were ESBL-positive and 96.3% of the ESBL-producers were MDR. Among the ESBL-producers, 100% harbored bla CTX-M , 63% harbored bla SHV , and 11.1% harbored bla TEM genes. ESBL-producers showed a higher level of resistance to the tested cephalosporins, fluoroquinolones, trimethoprim-sulfamethoxazole, and tetracycline than non-ESBL producers. All isolates were resistant to the tested penicillins. Prevalence of resistance to about two-third of the tested antibiotics was higher than 50% and 93.6% of the isolates were MDR. High prevalence of virulence factors particularly the adhesins (82.1% csgA, 73.1% fimH genes) and siderophore (73.1% sitA gene) was seen in the UPECs. But fortunately in MDR isolates, the virulence score and prevalence of hemagglutinin (tsh), hemolysin toxin (hlyD) and invasin (ibeA) genes were lower than in non-MDR UPECs. Shockingly, among the 15 common antibiotics, only nitrofurantoin (<20% resistance) could be recommended as an appropriate drug for the treatment of UTIs due to our ESBL-producer UPECs. Conclusion: The alarming level of virulent MDR ESBL-producer E. coli strains in this study necessitates the performing of an antibiotic stewardship program, regional screening of ESBL-producers and their virulence properties to select appropriate antibiotic, or designing new therapeutic methods for UTIs by inactivation of the essential virulence factors of UPECs.

Background Salmonella enterica serovar Enteritidis (S. Enteritidis) is one of the most common serovars, associated with human salmonellosis. The food-borne outbreak of this bacterium is mainly related to the consumption of contaminated poultry meat and poultry products, including eggs. Therefore, rapid and accurate detection, besides investigation of virulence characteristics and antimicrobial resistance profiles of S. Enteritidis in poultry and poultry egg samples is essential. A total of 3125 samples (2250 poultry and 875 poultry egg samples), sent to the administrative centers of veterinary microbiology laboratories in six provinces of Iran, were examined for Salmonella contamination, according to the ISO 6579 guideline. Next, duplex PCR was conducted on 250 presumptive Salmonella isolates to detect invA gene for identification of the genus Salmonella and sdf gene for identification of S. Enteritidis. Subsequently, the S. Enteritidis isolates were examined for detection of important virulence genes (pagC, cdtB, msgA, spaN, tolC, lpfC, and spvC) and determination of antibiotic resistance patterns against nalidixic acid, trimethoprim-sulfamethoxazole, cephalothin, ceftazidime, colistin sulfate, and kanamycin by the disk diffusion method. Results Overall, 8.7 and 2.3% of poultry samples and 6.3 and 1.3% of eggs were contaminated with Salmonella species and S. Enteritidis, respectively. The invA and msgA genes (100%) and cdtB gene (6.3%) had the highest and the lowest prevalence rates in S. Enteritidis isolates. The spvC gene, which is mainly located on the Salmonella virulence plasmid, was detected in 50.8% of S. Enteritidis isolates. The S. Enteritidis isolates showed the highest and the lowest resistance to nalidixic acid (87.3%) and ceftazidime (11.1%), respectively. Unfortunately, 27.0% of S. Enteritidis isolates were multidrug-resistant (MDR). Conclusion The rate of contamination with Salmonella in the poultry and egg samples, besides the presence of antimicrobial resistant and MDR Salmonella isolates harboring the virulence genes in these samples, could significantly affect food safety and subsequently, human health. Therefore, continuous monitoring of animal-source foods, enhancement of poultry farm control measures, and limiting the use of antibiotics for prophylactic purposes in food producing animals, are essential for reducing the zoonotic risk of this foodborne pathogen for consumers and also choosing effective antibiotics for the treatment of salmonellosis.

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It is common knowledge that fecal microbiota is a primary source of Escherichia coli causing urinary tract infections (UTIs) via the fecal‐perineal‐urethral route. But, it is still unknown whether E. coli UTI is mainly caused by dominant fecal E. coli isolates (prevalence hypothesis) or the isolates that possess more virulence factors (special pathogenicity hypothesis). In the present study, the urine E. coli isolates of 30 women with UTI were compared with the fecal E. coli isolates of the same patients and healthy control individuals according to the phylogenetic group, virulence genotype, and antibiotic susceptibility pattern. The genetic relatedness of the isolates was specified and compared by pulsed‐field gel electrophoresis (PFGE). PFGE analysis showed that most patients (73.3%) had distinct urine isolates which were not similar to any of their fecal isolates. Based on the phylogenetic analysis, most of the urine and fecal isolates of healthy women were assigned to phylogenetic group B2, followed by D. The distribution of phylogenetic groups was significantly different between the urine and the fecal isolates of patients ( p < 0.05). The prevalence of fimH and ompT among urine isolates was significantly more than that among fecal isolates. The level of multidrug resistance was higher among urine isolates. Although more in‐depth researches are required, the present study could be supported by pathogenicity hypothesis. Furthermore, concerning the antibiotic resistance pattern among uropathogenic E. coli should be highly considered.

Due to the importance of canine pathogenic E. coli reservoir hypothesis, close contacts between humans and dogs raises public health concerns. Determining the rate of cross-species bacterial sharing and confirm its accuracy by different fingerprinting techniques will help to find ways for reducing the economic impact of E. coli infections. This study support claims that public health concerns regarding the cross-species sharing of E. coli are warranted but this risk is minimal.