Endemic Hemolytic Uremic Syndrome in Children in Oklahoma

Objective: To characterize the epidemiology, clinical characteristics, treatment, and outcomes of hemolytic uremic syndrome in children in Oklahoma.

Introduction: Hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure in children worldwide, and is defined by a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. Typical HUS is characterized by a prodrome of diarrhea (often bloody) that is caused by a Shiga-toxin producing organism such as Escherichia coli 0157:H7. Recent E.coli 0157:H7 outbreaks causing HUS have received great media attention. However, the majority of cases of HUS may be endemic, not associated with an identified outbreak. Methods: All patients at Children's Hospital of Oklahoma from 2003-2005 with an ICD-9 discharge code of 283.11 (HUS) were identified. Medical records were available and evaluated for 18 of 19 patients.

Results: Cases occurred in all three years of the study: eight in 2003, four in 2004, and six in 2005. The average age of these patients was 4.4 years, 13 were female, and 12 were Caucasian. Sixteen patients had a diarrhea-prodrome; in 13 the diarrhea was bloody. E.coli 0157:H7 was isolated from only four of the patients' stool samples. Ten patients required dialysis; five patients were treated with plasma exchange therapy. All survived. Conclusions: Endemic HUS accounted for all cases in children in Oklahoma from 2003-2005, and is an important cause of childhood morbidity.