Rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method

AIM: To develop a new, rapid and accurate reverse dot blot (RDB) method for the detection of intestinal pathogens in fecal samples.METHODS: The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escherichia coli O157:H7, Clostridium botulinum, Bacillus cereus, Clostridium perfringens, Vibrio parahaemolyticus, Shigella spp., Yersinia enterocolitica, Vibrio cholerae, Listeria monocytogenes and Staphylococcus aureus. The two universal primers were designed to amplify two variable regions of bacterial 16S and 23S rDNA genes from all of the 12 bacterial species tested. Five hundred and forty fecal samples from the diarrhea patients were detected using the improved RDB assay.RESULTS: The methods could identify the 12 intestinal pathogens specifically, and the detection limit was as low as 103 CFUs. The consistent detection rate of the improved RDB assay compared with the traditional culture method was up to 88.75%.CONCLUSION: The hybridization results indicated that the improved RDB assay developed was a reliable method for the detection of intestinal pathogen in fecal samples.