Background:Hemolytic uremic syndrome (HUS) is a main cause of acute renal failure in children.This study aimed to analyze the clinical characteristics of HUS.Methods:A retrospective analysis was performed in 46 children with sporadic HUS.Results:Of the 46 HUS patients,20 (43.5%) were diarrhea-related HUS,and 26 (56.5%) were atypical HUS.Anemia,edema,oliguria,hemoglobinuria and hypertension were the most common manifestations.Thrombocytopenia,hyponatremia,hypocalcemia,hyperkalemia,metabolic acidosis,increased fibrinogen and hypocomplementemia were found in most patients.The age of onset (younger than 2 years or not,P=0.009),the duration of oliguria or anuria (more than one week or not,P=0.005),accompanied with extrarenal complications or not (P=0.005),dialysis and plasma exchange (P=0.04) were associated with the mortality rate.Conclusion:The age of onset younger than 2 years,oliguria/anuria more than 1 week,and associated with extrarenal complications were predictive factors of poor prognosis.