McKee RS, Schnadower D, Tarr PI, et al. - In view of the leading causative role of shiga toxin–producing Escherichia coli (STEC) infections in pediatric acute renal failure, researchers sought hemolytic uremic syndrome (HUS) risk factors to guide care. In this multicenter, historical cohort study, 927 STEC-infected children were assessed. Of these, 41 (4.4%) presented with HUS; of the remaining 886, 126 (14.2%) developed HUS. STEC infection was identified to be of complex nature which renders predicting its course a challenge. Younger age, leukocyte count ≥ 13.0 × 10³/μL, higher hematocrit and serum creatinine, platelet count < 250 × 10³/μL, lower serum sodium, and intravenous fluid administration initiated ≥ 4 days following diarrhea onset were identified as predictors of HUS. Reduced HUS risk was observed in correlation with a longer interval from diarrhea onset to index visit. Female gender, younger age, lower serum sodium, higher leukocyte count ≥ 13.0 × 10³/μL and creatinine concentrations, and initial intravenous fluid administration ≥ 4 days following diarrhea onset were RRT predictors.