Five patients with severe hemolytic uremic syndrome (HUS) were followed for 10-18 years. Because of proteinuria, arterial hypertension, and reduced glomerular filtration rates, they received either captopril (n=2) or enalapril (n=3), or both (n=1) for 8-15 years. Blood pressure was normalized and proteinuria reduced in all; glomerular filtration improved in three patients and fell moderately in two. Four of the five patients have reached adult age with body weight and height, blood pressure, and serum creatinine levels within the normal range. At the last evaluation, median proteinuria was 220 mg/24 h (range 0-310) and glomerular filtration rate 56 ml/min per 1.73 m(2)(range 40-127). This long-term study indicates a renoprotective effect of angiotensin-converting enzyme inhibitors in patients with sequelae after HUS.