title: Risk of hemolytic uremic syndrome after sporadic Escherichia coli O157:H7 infection: results of a Canadian collaborative study. Investigators of the Canadian Pediatric Kidney Disease Research Center.
abstract: OBJECTIVE
  The objectives of this study were to better estimate the age-specific risks of hemolytic uremic syndrome (HUS) and hemolytic anemia after Escherichia coli O157:H7 infection among a representative cohort of both referred and nonreferred children with documented illness from the province of Alberta and to compare this with the rates in children evaluated at referral centers in the rest of Canada.
  
  
  METHODS
  Children with HUS or E. coli O157:H7 gastroenteritis were eligible if they were < 15 years of age. Hemoglobin, blood smear, urinalysis, and serum creatinine were obtained 8 to 10 days after the onset of diarrhea to ascertain for hemolysis, anemia, thrombocytopenia, and renal injury. Subjects were monitored for 1 month.
  
  
  RESULTS
  From June 1991 to March 1994, HUS was diagnosed in 205 children. Of these 77% had evidence of E. coli O157:H7 infection. A further 582 children had E. coli O157:H7 gastroenteritis, of whom 18 had hemolytic anemia. The risk of HUS after E. coli O157:H7 infection in Alberta was 8.1% (95% confidence interval, 5.3 to 11.6) compared with 31.4% in referral centers in the rest of Canada. In Alberta the highest age-specific risk of HUS/hemolytic anemia was 12.9% in those < 5 years of age.
  
  
  CONCLUSIONS
  These data will help guide clinical care and provide a basis for estimating the sample sizes required in future treatment trials for the secondary prevention of HUS.
authors.affiliation: Canadian Pediatric Kidney Disease Research Center, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada.
authors.forename: P C
authors.initials: PC
authors.lastname: Rowe
authors.forename: E
authors.initials: E
authors.lastname: Orrbine
authors.forename: H
authors.initials: H
authors.lastname: Lior
authors.forename: G A
authors.initials: GA
authors.lastname: Wells
authors.forename: E
authors.initials: E
authors.lastname: Yetisir
authors.forename: M
authors.initials: M
authors.lastname: Clulow
authors.forename: P N
authors.initials: PN
authors.lastname: McLaine
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000416:Alberta / Q000453:epidemiology; D000743:Anemia, Hemolytic / Q000453:epidemiology / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood; D004927:Escherichia coli Infections / Q000150:complications* / Q000382:microbiology; D019453:Escherichia coli O157; D005260:Female; D006463:Hemolytic-Uremic Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D007223:Infant; D008297:Male; D012307:Risk Factors
chemical_list: D003404:Creatinine