[Detection of enterotoxigenic Escherichia in patients with diarrhea of undetermined etiology using experimental...

Feces from 249 adult patients hospitalized due to diarrhea of unknown etiology were investigated. In 65.5% of the patients enterotoxic E. coli (ETEC) producing thermostable enterotoxin were detected by the anal test in suckling mice. As demonstrated by the paw edema test in mice, 79% of such strains produced also thermolabile enterotoxin, the remaining strains belonged to the ETEC variants, known from the literature, producing only thermostable enterotoxin. The antigenic similarity of the thermolabile enterotoxin with cholerogen was confirmed by the phenomenon of paw edema neutralization in mice. Among the cultures isolated from the patients 2 ETEC variants, which could not be differentiated by the test in suckling mice and by the paw edema test in mice and paw edema neutralization, were detected by the intranasal infection of mice.