Hemolytic uremic syndrome due to Escherichia coli O157: H7 in a child with multiple infections.

Hemolytic uremic syndrome (HUS) is characterized by hemolytic anemia, thrombocytopenia, and uremia; it is a common cause of acute renal failure in children. Although many microbial agents have been associated with HUS, only Escherichia coli O157: H7 has been clearly demonstrated to be a major cause of this illness. A case is presented of a healthy 4-year-old boy who had a recent varicella infection; when evaluated for HUS his blood and stool cultures both grew Salmonella montevideo and blood cultures grew group A beta-hemolytic streptococci. A stool cultured on MacConkey-sorbitol agar also grew E. coli O157: H7. An eightfold rise in serum antibodies to E. coli O157: H7 lipopolysaccharide was also demonstrated. The child recovered completely and was healthy 3 years later. Although this child had several infectious agents anecdotally associated with HUS, appropriate culture of stool showed that he also had E. coli O157: H7 infection. Previous cases thought to be due to other pathogens may similarly have been caused by co-infection with E. coli O157: H7.