No large cohort study has yet determined the incidence of acute kidney injury (AKI) in children with heart failure treated with renin-angiotensin system (RAS) inhibitors. We thus retrospectively analyzed the incidence and risk factors for severe AKI (stages 2-3 according to the Kidney Disease Improving Global Outcomes (KDIGO) guidelines) at our institutions from 2008 to 2011. Among 312 children (162 boys; median age, 7.3 months), 59 cases of AKI occurred in 45 children. The incidence of AKI was 14.3 cases per 100 person-years overall (follow-up 413.6 person-years), or 27.3, 16.8, and 4.5 cases per 100 person-years in children aged < 1, 1-3, and a parts per thousand yen4 years, respectively. Among them, 23 (39.0 %) children had metabolic acidosis and 14 (23.7 %) had hyperkalemia. Younger age, myocardial disease, cyanotic congenital heart disease, use of spironolactone, and cardiac surgery were independent risk factors for AKI. Furthermore, 37.3 % of children suffered dehydration during AKI.
Conclusion: AKI incidence is relatively high in children, particularly younger children, with heart failure treated using RAS inhibitors. Careful monitoring of renal function and serum electrolytes is essential. Proper management of fluid balance after infection and cardiac surgery may reduce the risk of AKI. Temporary discontinuation in RAS inhibitors should be considered during dehydration or surgery.