GENETIC AND PHENOTYPIC ANALYSIS OF ESCHERICHIA-COLI WITH ENTEROPATHOGENIC CHARACTERISTICS ISOLATED FROM SEATTLE CHILDREN

Coliform colonies from children whose stools were submitted for microb iologic analysis were studied prospectively to determine the frequency of shedding of enteropathogenic Escherichia coil (EPEC). In total, 22 25 isolates from 445 patients were probed with eaeA (encoding intimin) and the EAF (EPEC adherence factor) probe, and adherence and actin-ag gregating phenotypes were determined. Twenty-five patients (5.6%) shed non-O157:H7 eaeA(+) EAF(-) E. coli. Of these 25 patients, isolates fr om 5 produced Shiga toxins and from 3 possessed bfpA (encoding the bun dle-forming pilus) sequences. Non-O157:H7 eaeA(+) E. coli from 21 (84% ) of 25 patients adhered locally to and aggregated actin in HeLa cells . Four patients shed nonadherent EAF(+) eaeA(-) E. coli. Non-O157:H7 e aeA(+) and EAF(+) isolates belonged to diverse electrophoretic types a nd classical and nonclassical enteropathogenic serotypes. EPEC are rel atively common in stools submitted for analysis in this North American pediatric hospital. Their etiologic role in childhood diarrhea warran ts elucidation.