Patient 2

Patient 2 - Daphne

Principles of Faecal Culture:

A variety of bacterial and viral agents may cause diarrhea. Since faeces consist of a large number of bacteria, the potential bacterial pathogens may be overgrown by normal faecal flora when cultured on nonselective media. To enhance isolation of faecal pathogens, selective, differential and enrichment media are used. Screening of faeces should be routine for Salmonella, Shigella, Campylobacter and Vibrio spp. The role of Aeromonas and Plesiomonas spp in causing diarrhea is controversial and these are reported only when heavily grown in pure cultures. On occasions, enteropathogenic E.coli (EPEC) cause problems in neonatal outbreaks and like other diarrhoegenic E.coli, are not readily detected by current reagents and media. Where indicated, Yersinia spp, enterohaemorrhagic E.coli and C.difficile may be cultured as well. Food-handlers are also screened for Salmonella spp as is required by the licensing unit of the Ministry of Environment (Singapore).