Hemolytic uremic syndrome epidemiology: a population-based study in King County, Washington, 1971 to 1980.

We conducted a retrospective, population-based study of the hemolytic uremic syndrome of childhood in King County, Washington. The average annual incidence of hemolytic uremic syndrome between 1971 and 1980, inclusive, was 1.16 cases per 100,000 children younger than 15 years of age and increased during the decade and into the early 1980s. The highest annual incidence was in children less than 3 years of age (3.02 per 100,000 children) and was equal in black and white children. No demographic risk factors were associated with the incidence of this disease including population density, median family income, crowding in housing units, percentage of households with public water supply, and percentage of households with public sewers. Our data suggest that this disease is common, endemic, and increasing in incidence in King County, Washington.