The prevalence of Diarrheagenic Escherichia coli and Shigella species isolated from patients with gastroenteritis infection referred to Shiraz University of Medical Science hospital (2018-2019)

Introduction and Objectives: Diarrheal illnesses are a severe public health problem and a major cause of morbidity and mortality in infants and young children, especially in developing countries. A number of different bacterial pathogens such as Shigella and diarrheagenic Escherichia coli (DEC) with different frequency patterns are isolated as the causes of acute diarrhea in both developed and developing countries. This study was conducted to find the etiology of acute diarrhea in infants and young children.Materials and Methods: Included in this study were children under the age of 15 who, complaining about diarrhea, referred to the emergency wards of two major hospitals in Shiraz (i.e., Dastgheyb and Namazi). All stool samples were investigated for Salmonella, Shigella, and DEC. To identify Shigella and different groups of E. coli, their associated specific primers were utilized. Results: A total of 300 samples from patients with acute diarrhea were analyzed. The most common (48/190 or 25.2% of positive cases) was DEC and the most prevalent of which were the groups EPEC, EAEC, EIEC, and ETEC comprising 35.4%, 33.3%, 20.8%, and 10.4% of DEC cases, respectively. Out of the 50 Shigella isolates, 34 (68%) isolates were identified as S. sonnei, 15 (30%) serotypes were identified as Shigella flexneri, 1 (2%) serotypes were identifed as Shigella boydii. Conclusion: This study suggests that EPEC and Shigella strains are important contributors to diarrhea in Iranian children. Because of the weakness of routine microbiological tests and poor specifity of serological tests, it is recommended that the EPEC and Shigella strains are better detected by molecular methods.

Keywords:

Diarrheagenic Escherichia coli (DEC) , Shigella , enteropathogenic , acute diarrhea