[The relationship of Coli strains and hemolysis in diarrhea]

In the majority of diarrheal diseases no causative bacterial organism can be identified. Enteropathogenic E.-Coli-Strains were incriminated as causative agents in gastroenteritis on a epidemiologic basis, no pathogenetic mechanisms could be attributed. Cholera research initiated a new understanding of the pathogenesis of E. coli diarrheas: An enterotoxin was found which stimulated fluid and electrolyte secretion in the intestine. We were able to grow E.-Coli-Strains with hemolysis in a number of infants with severe, longstanding diarrheas. As the plasmids for hemolysis, enterotoxin production and adhesiveness of organisms on the intestinal mucosa is frequently transmitted simultaneously, we expected to find the majority of enterotoxic strains in the group of E. coli with hemolysis. 12 out of 100 strains E. coli with hemolysis isolated from diarrheal stools were enterotoxin producing strains. Enterotoxic strains were found almost exclusively in infants under one year of age with intractable diarrhea. We conclude therefore that enterotoxic E.-Coli-Strains are real causes of diarrhea also in our region and not as usually assumed only in the tropics. Furthermore, enterotoxic E.-Coli-Strains are found predominantly in the group of E. coli with hemolysis. Other biochemical and serological tests offer no additional possibilities for identification. Possibly also other pathogenetic mechanisms for E. coli with hemolysis might exist for acute diarrheas, however they are not sufficiently investigated yet.