Non-O157:H7 Stx2-Producing Escherichia coli Strains Associated with Sporadic Cases of Hemolytic-Uremic Syndrome in Adults

From August 1996 to May 1997, six verotoxin-producing Escherichia coli (VTEC) strains were isolated from stool specimens of adults suffering from hemolytic-uremic syndrome (HUS). All the isolates were stx(2) positive and belonged to different serotypes: O6:H4, O91:H10, O91:H21, O rough:H16, OX3:H−, and O nontypeable:H−. The enterohemolysin (Ehly)-encoding genes were detected in two isolates, and none of the isolates harbors the intimin (Eae)-encoding gene. These findings suggest that stx(2)-positive non-O157:H7 VTEC is a major cause of HUS in adults and that several sources of pathogens are responsible for local endemic infections.