Increasing frequency of acute kidney injury amongst children hospitalized with nephrotic syndrome

Nephrotic syndrome (NS) is among the most common kidney diseases seen in children. The major complications of NS include infection, acute kidney injury (AKI), and thromboembolism (TE). The objective of this study was to analyze long-term trends in the epidemiology of major complications of pediatric NS. We used the Healthcare Cost and Utilization Project Kids' Inpatient Database for the years 2000-2009 to perform an analysis of U.S. hospitalizations of children diagnosed with NS with or without infection, AKI or TE. The frequency of NS hospitalizations complicated by AKI increased by 158 % between 2000 and 2009 (p < 0.001). The frequency of NS hospitalizations with infection and TE remained stable overall. Pneumonia was the most common infectious complication while peritonitis decreased by 50 % (p < 0.001). Importantly, development of any of these major complications of NS resulted in similar to 2-3-fold increases in both hospital charges and length of stay. It is concerning that the frequency of AKI in children hospitalized with NS has more than doubled in the past decade. Strategies to prevent or initiate earlier treatments for complications of NS could have a major impact on both morbidity and health care expenses.