Less than 25% of infants with acute diarrheal disease have isolatable causative pathogens. In this study 4 children with enteropathogenic Escherichia coli (EPEC) and 8 children with nonspecific diarrhea (NSD) were studied to determine any changes in bile acid metabolism glucose absorption and intestinal microflora. Bile acid patterns in the duodenum and feces were altered in children with NSD. Glucose absorption was significantly reduced in NSD patients whereas it was normal among children suffering from EPEC. Cultures obtained by anaerobic aspiration of the duodenum revealed an increased concentration of anaerobic flora in NSD patients. However no differences in aerobic or facultative anaerobic flora were evident. NSD and EPEC groups both had increased jejunal water secretion but children with acute NSD had a more profound change in intestinal function as shown by alterations in intestinal microflora secondary bile acid production and glucose transport.