International Journal of Enteric Pathogens
Volume:2 Issue: 1, Feb 2014

Shiga toxin-producing Escherichia coli (STEC) have emerged as the important zoonotic food-borne pathogens and confirming the risk to public health. Enteropathogenic Escherichia coli (EPEC) is a major cause of children diarrhoea in developing countries. E. coli strains can be assigned to four main phylogenetic groups, A, B1, B2 and D.. The aim of the current study was to analyze the distribution of phylogenetic groups and presence of STEC and atypical EPEC pathotypes in E. coli isolated from human diarrhea and fecal samples of healthy cattle in Kerman, Iran by PCR.. A total of 188 E. coli isolates were isolated from human diarrheic (94 isolates) and fecal healthy cattle (94 isolates) samples. The isolates were confirmed by standard bacteriological tests. The confirmed isolates were examined to detect the phylogenetic groups and a selection of virulence genes including stx1, stx2 and eae by PCR.. Phylotyping of isolates from diarrheic human showed that 38.29% belonged to A, 20.21% to B1, 14.89% to B2 and 26.59% to D phylo‐groups. The isolates of healthy cattle distributed in A (34.04%), in B1 (47.88%), in B2 (7.44 %) and in D (10.64%) phylo-groups. Prevalence of eae gene in human diarrheic isolates was 5.32% (5 isolates), whereas none of the human diarrheic isolates were positive for stx1 and stx2 genes. Among isolates of cattle 7.44% (7 isolates) were positive for stx1 gene and 5.32% (5 isolates) possessed eae gene. Of the all isolates examined, none were positive for the stx2 gene. The eae gene were positive for isolates of human diarrhea distributed in A and B2 phylo-groups and isolates possessed stx1 and eae genes from healthy cattle fell into A (4 isolates), B1 (7) and B2 (one isolate).. The isolates of human diarrhea samples and fecal healthy cattle were distributed into different phylogenetic groups, which mostly distributed in A and B1 phylo-groups. In addition, results of this study revealed the lower prevalence of SETC and aEPEC in isolates..

Clostridium difficile is the most important anaerobic, gram positive, spore forming bacillus which is known as a prevalent factor leading to hospital diarrheas and is the causative agent of pseudomembrane colitis. The role of this bacteria along with the over use of antibiotics have been proved to result in colitis. The major virulence factors of these bacteria are the A and B toxins.. The purpose of this study was to isolate C. difficile from stool samples and detect A and B toxins encoding genes, in order to serve as a routine method for clinical diagnosis.. Recognition of A and B toxins encoding genes by uniplex and multiplex PCR using two pairs of primers from 136 accumulated stool samples.. Results of the present study showed that out of 136 stool samples, three C. difficile were isolated and these strains contained A and B toxins encoding genes.. It wasconcluded that although detection of C. difficile from stool samples based on PCR (polymerase chain reaction) is expensive, yet this method is more sensitive and less time-consuming than culture methods and can be used as a clinical laboratory test..

Helicobacter pylori (H. pylori) is a gram-negative, spiral-shaped, microaerophilic microorganism and a causative agent of many gastrointestinal tract diseases, as well as several extragastric infections. Several studies have suggested the possibility of sexual transmission of these bacteria.. The aim of the current study was to determine the possibility of detecting H. pylori DNA in semen samples from infertile men, compared with healthy controls..Patients and One hundred infertile male patients and 100 age and gender-matched healthy controls have been enrolled in the study. Semen samples collected from each participant, undergone DNA extraction and polymerase chain reaction (PCR) assay to detect the H. pylori. The ß-actin PCR was performed to verify the accuracy of DNA extraction.. Each sample was positive in the ß-actin PCR assay. None of the samples, from both patients and controls, showed positive PCR results. Consequently, statistical analysis was impossible to perform.. We could not confirm the presence of H. pylori DNA in semen samples, but this does not exclude the possibility of male urethral colonization by this organism. Further studies with similar results are necessary to certify this hypothesis..

The paper entitled “Antibiotic Resistance Pattern of Escherichia coli Groups A, B1, B2 and D Isolated from Frozen Foods and Children with Diarrhea in Sanandaj, Iran” published in International Journal of Enteric Pathogens 2013.1 (1), is a short, simple article that discusses original research conducted on E. coli strains isolated from 125 samples of frozen food from animal sources, and 466 rectal swabs from children with diarrhea. Certainly, such periodic surveys conducted on various samples that may have a major role in the spread of pathogenic bacteria would shed light on the susceptibility of pathogens and help in the containment of spread of infections in hospital environments as well as in the community..In recent years, the spread and acquisition of antibiotic resistance genes between different species of disease causing bacteria has been on the rise. Among these bacteria, strains of E. coli have gained worldwide attention and their pattern of antibiotic resistance has been a subject of controversy among specialists of the field. The existence of four distinct sub-species within E. coli has been established; these are designated A, B1, B2 and D (1) that can be divided into seven subgroups (A, A1, B1, B22, B23, D1 and D2), according to the combination of the three genetic markers chuA, yjaA and DNA fragment TspE4.C2 (2). Thus, this study would have been better if they had determined the other three subgroups. Therefore, phylo-group determination can reveal a great deal regarding sub-group membership..Based on the available databases, it has been found that E. coli extrapathogenic phylo–group strains are globally disseminated and drug resistant with a broad range of human hosts (3, 4). Further studies are needed to characterize their origins, virulence mode of actions, geographical distribution, clinical associations and modes of dissemination. The findings of the study conducted on frozen food samples of animal origin and rectal swabs from children with diarrhea in the city of Sanandaj by Kalantar et al., are interesting and can be helpful as a reference for future studies for comparative purposes

The increasing prevalence of antimicrobial resistance bacteria in meat-producing animals, especially ruminants, represents a major problem for human and veterinary medicine and also could increase the patients'' morbidity and mortality.. The current study aimed to identify the occurrence and antimicrobial susceptibility pattern of Salmonella spp. and Escherichia coli isolated from slaughtered ruminants in East-Azarbaijan province.. In this study 160 samples (40 sheep, 40 goats and 80 cattle) were examined to isolate the enteric pathogens. The antibiotic resistance was determined by Kirby-Bauer disc diffusion method using 12 antibiotics.. A total of one hundred and twenty bacteria were obtained and most of these isolates belonged to these following genera: Escherichia coli (25%), Proteus (18.8%), Salmonella spp. (8.8 %), Pseudomonas spp. (7.5%) and Yersinia spp. (6.3%). Eight (57.1%) of 14 Salmonella spp. isolates and 26 (65%) of 40 E. coli isolates showed resistance to more than four antibiotics, called multiple antibiotic resistance (MAR).. Overall, the obtained results emphasize the need for a surveillance and monitoring system to emerge drug resistance in all pathogenic microorganisms in ruminant and other animals.

Among the most common infectious diseases, second ranking after respiratory (tract) system infection is urinary tract infection which involve (infects) about 250 million people in developing countries annually.. The purpose of this study is to investigate the pattern of antibiotic resistance in common pathogens that cause urinary tract infection. This study is the first to evaluate the incidence of antibiotic resistance is the large number of samples in IRAN.. Patients and The susceptibility of samples obtained from 14,332 patients with urinary tract infections admitted to different medical diagnostic laboratories of Tehran, was measured using disk diffusion method for 18 common antibiotics.. Most of the identified bacteria were Escherichia coli (64.56%) and Klebsiella pneumoniae (13.78%).The most resistant antibiotics were respectively identified as trimethoprim/ sulfamethoxazole (61.35%) for E-coli and (49.6%) for Klebsiella sp. Also intermediate resistance to Nitrofurantion and Chlortetracycline was observed.. The findings of this study indicate that E. coli is the predominant pathogen of this infection. There are also bacteria with high resistance that Interfere with prescription of drugs in order to treat urinary tract system infection. Also increasing of resistance to drugs among bacterial pathogens is evolving and requires an inspectoral and research procedure which could provide more information for doctors to treat the infection more efficiently..

Detecting enteric bacteria in blood by culture is a slow assay with low accuracy rate. PCR might be a suitable alternative assay but as several species can cause bacteremia, it is necessary to use universal primers.. In this study we evaluated and compared two pairs of universal primers in detecting four enteric bacteria in blood, which are common causes of bacteremia in human.. Standard strains of E. faecalis, S. typhi, E. coli, and S. Aeruginosa, were used in this study. A serially diluted bacterial suspension of all strains was made for inoculation to four sets of defibrinated sheep blood which were used to prepare blood specimens with different bacterial contents for performing routine assay and PCR. PCR was performed using two different universal primers designed from two ribosomal genes, 16sr RNA and 23sr RNA.. PCR with 16sr RNA universal primer showed more accuracy rate than both blood culture and PCR with 23sr RNA universal primer. Mean time for performing PCR assay and blood culture was eight and 48 hours, respectively... Both PCR with 16sr RNA and 23sr RNA universal primers have more accuracy rate than blood culture and are faster in detection of bacteremia. PCR with16sr RNA universal primer is more accurate than both PCR with 16sr RNA universal primer and blood culture for diagnosis of bacteremia..

Brucellosis is an endemic infectious disease in Iran. Prevention strategies are based upon identification of risk factors for brucellosis.. The purpose of this study was to determine the principal risk factors for brucellosis in Khuzestan Province, Southwestern Iran..Patients and In this retrospective study, the medical records of 162 admitted patients, 81 brucellosis cases and 81 controls with other unrelated conditions, were reviewed. The study was undertaken in the Razi Hospital, Teheran, IR Iran, a university hospital where infected patients throughout Khuzestan are refereed. The diagnostic criteria of the disease were the Wright test and 2-Mercaptoethanol (2ME) agglutinin assay with titers greater than 1:160 and 1:80, respectively, and clinical symptoms compatible with brucellosis. Statistical analyses were performed with the SPSS 16.0 software. Univariate analysis was performed by calculating the odds ratio (OR) and the 95% confidence interval (CI) to compare cases and controls for each variable.. Of a total of 81 patients with brucellosis, 38 (46.8%) had had direct contact with animals, 47 (58%) had consumed high risk foods, and 48 (59.2%) were from rural areas. Analysis showed that brucellosis had a significant association with untreated milk consumption (OR 5.57, 95% CI = 1.77–17.08, P = 0.002), slaughtered meat (OR: 8.77, 95% CI = 1.07–71.81, P = 0.03), direct contact with animals and individuals who had a nomadic lifestyle (OR: 3.57, 95% CI = 1.34–9.54, P = 0.01).. In the studied region, the main risk factors for brucellosis are: consumption of untreated milk/dairy products, slaughtered meat and direct contact with animals. Therefore, improved veterinary services and public health education are a requisite to control the disease..

Probiotics are live microbial supplements which can improve the healthy intestinal microbial balance. Lactobacilli are a group of lactic acid producing bacteria (LAB) that are known as natural probiotics found in the dairy products.. In this study, we aimed to detect the most potent Lactobacillus isolates of the Fars province local dairy products in cholesterol removal and investigate their antibacterial properties against some gastrointestinal pathogens..Materials and Fifteen locally produced yogurt samples of the Fars province were collected and characterized with routine microbiology methods. Cholesterol removal ability of the lactobacilli isolates were determined, and their growth inhibitory effect on some standard pathogenic strains pathogen was evaluated using the well-diffusion method.. In this study, five common strains of lactobacilli including L. acidophilus, L. casei, L. fermentum, L. lactis, and L. bulgaricus were identified in the samples obtained from the locally produced yogurt in the Fars province. L. lactis and L. acidophilus were determined as the two most active strains with the maximum rate of cholesterol assimilation (5.6 and 4.5 mg/mL, respectively) in the process of cholesterol removal. In the antibacterial activity assay, the two mentioned strains had significant inhibitory effect on all of the tested bacteria except for B. subtilis.. Cholesterol removal ability had a direct relation with bacterial growth, so it is suggested to use the probiotic bacteria in the growth phase to achieve better results..

Diarrhea is an important cause of illness and death among all age groups on a global scale. Enterotoxigenic Escherichia coli (ETEC) protozoans were established as a causative agent of diarrhea in developing and developed countries. The identification of diarrheagenic E. coli (DEC) strains needs to detect the factors that determine the virulence of these organisms.. In this study, we aimed to use the multiplex real-time (MRT) and multiplex PCR assays for identification of ETEC in patients with diarrhea in Shiraz, Iran..Patients and A total of 430 stool samples were collected from patients with diarrhea in Shiraz, in 2012. Diarrheagenic E. coli (DEC) strains were isolated by standard biochemical analysis. We used MRT-PCR and multiplex PCR (MPCR) assays to detect the presence of LT, STΙa and STΙb genes in ETEC.. In this study, 430 stool samples were tested and 52 (12.1%) were identified as contaminated with E. coli using standard biochemical tests. The ETEC were detected in eight patients (15.4%) with diarrhea by the MRT-PCR and MPCR methods. The results of this study showed that four out of eight strains (50%) were STΙa producer, and three out of eight strains were ST producers (37.5%). Also, one strain (12.5%) contained both STΙa and LT genes, simultaneously.. This is the first study performed in Shiraz to identify ETEC intestinal pathogens in patients with diarrhea. The results of this study showed that MRT-PCR can be used as a replacement for the conventional MPCR assay to detect the ETEC strains.