Background: Gastroenteritis is a remarkable hygiene problem worldwide. Bacteria and parasites can cause gastroenteritis-associated disorders.Objectives: The aims of study were to survey the most common cause of gastroenteritis in patients referred to Imam Khomeini Hospital of Ilam, Iran.Patients and Methods: This descriptive-analytical study was performed during 2012 to 2013. After collecting 2376 stool samples, standard biochemical and microbiological tests were performed. Susceptibility was tested by disc diffusion method agreeing with clinical and laboratory standards institute (CLSI) guidelines. The protozoa were detected by sediment wet-mount method.Results: Of 2376 patients, 466 (19.6%) were contaminated with pathogenic bacteria or protozoa. The frequency of microorganisms isolated from the patients were 10.3%, 2.5%, 2.5%, 2.1%, 46.4%, 30.9%, 2.5% and 2.5% for enteropathogenic Escherichia coli (EPEC), Shigella dysenteriae, Klebsiella pneumonia, Yersinia enterocolitica, Entamoeba histolytica, Giardia lamblia, E. coli and Candida spp., respectively. Sensitivities to ciprofloxacin in E. coli and S. dysenteriae strains were 100% and 91.66%, respectively.Conclusions: The results showed that some patients were probably contaminated with nonbacterial and nonparasitic agents. All the parasitic isolates were resistant to most antibiotics. Therefore determination of microbial isolates and antibiotic susceptibility is necessary before treatment procedures.

Background: Intestinal parasites are among the most common heath problems in most of the countries. Since it could be asymptomatic and also with respect to the role of environmental factors in this regard, the present study was conducted in Iran in the form of a national survey "health and disease" to determine the prevalence of intestinal parasites.Materials and methods: It was a cross sectional study. 1097 urban clusters (8776 families) and 590 rural clusters (4720 families) were selected through a random sampling. Stool exam was performed for subjects aged 2 years or above and the following intestinal parasites were examined: ascaris, giardia, entamoeba hystolitica, ancylostoma, taenia, tricocephal, etc. Then, the role of sex, age and site of infection was determined.Results: Of 53995 samples, 45128 samples were studies among which 45.8% were for males and 61% belonged to urban residents. Totally, 19.3% of the samples were infected where the infection rate was 19.7% in males and 19.1% in females. Giardia (10.9%) and ascaris (1.5%) were the most common protozoa and helminthes, respectively. Infection was revealed in 25.5% of subjects aged <25 years and 11.6% of subjects aged >70 years (p<0.000). Urban residents have lesser infectious disease Assistant professor, compared to rural residents (16.4% vs. 24.3%, p<0.000).Conclusion: Intestinal infection is quite common in Iran. With respect to its known side effects, the true etiology should be specified and preventive and therapeutic approaches should be considered.