Blood pressure in the long-term follow-up of children with hemolytic uremic syndrome

The hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure (ARF) in young children. Most patients recover from the acute phase of the illness but they may develop arterial hypertension (AH) after many years, even in the absence of signs of renal impairment during short-term follow-up. In this study, we performed casual blood pressure (BP) measurement, 24-h blood pressure monitoring (ABPM), and a Bruce walking treadmill study (ET) in 24 children (aged 5-15 years, 13 males, 11 females) with a history of HUS and normal renal function during follow-up (median 5.8 years, range 1.8-12.4 years). There were 22 children (91%) with prodromal diarrhea associated with HUS and 20 (83%) underwent dialysis during the acute illness. All children had normal casual BP measurement. Of 13 children (54%) with normal ABPM, 5 patients (38%) had an abnormal BP response during the ET study. There were 4 (58%) of the 7 patients with AH by ABPM (29%) and an abnormal BP response during ET. These findings suggest that ET could be a useful means of identifying children with a history of HUS that could be at risk of future AH even if they had normal renal function, casual BP, and ABPM during long-term follow-up. These results should be confirmed with a large prospective clinical study.