Optimisation of a method for isolation of Clostridium difficile from faeces
Clostridium difficile is a pathogen for both humans and animals and is often associated with antibiotic-associated diarrhea. Recently, several human cases of C. difficile-infection with increased mortality and morbidity have been reported. In studies performed in different countries C. difficile has been found in meat. Therefore the question whether C. difficile can be a zoonotic agent has been raised. The aim of this study was to optimize a method for isolation of C. difficile from faeces. When C. difficile is isolated from animals that do not have diarrhea the sample must be cultivated in an enrichment broth. Parameters influencing the enrichment were tested such as enrichment before and after spore selection, enrichment time, alcohol and heat chock for spore selection and if the samples had to be centrifuged or not before cultivation on agar plates. Enrichment in broth before spore selection was better than after. Heat and alcohol chock showed similar results, therefore you can chose which method you want. Cultivation from the pellet after centrifugation of the sample was better than cultivating directly from the inoculated broth. When the sample had low concentration of bacteria long enrichment time, 7 days or more, was best. The next step will be isolation of C. difficile from food-producing animals and humans and the strains will then be compared to se if the same strain is found in humans and in animals, to se if C. difficile-infection can be a zoonoz.