Hemolytic Uremic Syndrome and Diarrhea in Argentine Children: the Role of Shiga-like Toxins

Shiga-like toxin-producing Escherichia coli have been associated with hemorrhagic colitis and the hemolytic uremic syndrome (HUS). Because Argentina has the highest reported frequency of HUS in the world, Argentine children were prospectively studied during the HUS seasons for evidence of Shiga-like toxin-related diseases. On the basis of serology, fecal cytotoxin neutralization, stool cultures, and DNA hybridization of colony lysates, most children with HUS had evidence of infection with Shiga-like toxin-producing organisms. Children with spring-summer diarrhea also commonly (32%, confidence interval 18%-46%) had clear-cut evidence of such infection. No controls (children without gastrointestinal, renal, or hemolytic disease) had free fecal cytotoxin, positive cultures for E. coli O157:H7, or DNA probe-positive organisms; 20% of them had low serum titers of antibodies to Shiga-like toxins. E. coli O157:H7 was not common in either HUS or diarrhea patients. The high frequency of Shiga-like toxin-induced diarrhea in young children in Argentina probably explains the high incidence of HUS in this country and suggests that HUS is a relatively uncommon complication of Shiga-like toxin-related disease.