Yersiniosis in children.

40 cases of bacteriologically proved Yersinia enterocolitica infections in children under 15 years were reviewed. Most children presented with abdominal symptoms, and diarrhoea was present in 80% of them. In half of those with diarrhoea the stools were mucoid and gross blood was often present. Faecal leucocytes were found in 4 out of the 5 children studied. The clinical findings are consistent with the enteroinvasive pathogenic mechanism proposed for Y. enterocolitica. 29 of 30 faecal isolates of Y. enterocolitica were found invasive for human epithelial cells in vitro. Nine strains produced an enterotoxin demonstrable in newborn mouse assay. Toxin production may be an additional pathogenic mechanism in human yersiniosis.