IMPLICATIONS OF YERSINIA-ENTEROCOLITICA BIOTYPING

The utility of a simple biotyping scheme to differentiate pathogenic a nd non-pathogenic strains of Yersinia enterocolitica was determined fo r 79 patients who were admitted to or attended a reference children's hospital in western Canada. Biotyping defined predominantly two subset s of Y enterocolitica. 'Pathogenic' strains were more Likely to have b een obtained from younger patients (mean age 61.9 months) who experien ced an acute gastrointestinal illness that was occasionally associated with bloody diarrhoea or a surgical procedure. Growth of Y enterocoli tica from selective solid bacteriological growth media were often in t he moderate to heavy range (82.0%). In contrast, 'non-pathogenic' stra ins were more often obtained from older patients (mean 116.0 months) w ho were already recognised to have suffered from a chronic illness and who were likely to have been admitted to hospital. Moderate to heavy growth of bacterium in stool specimens were infrequently (17.4%) obtai ned from the latter patients. The use of a simple biotyping scheme for the differentiation of Y enterocolitica strains has the potential to improve patient care.