Chronic-on-acute kidney injury.

Although older teaching suggested that patients who survived an episode of acute kidney injury (AKI) had a benign course, recent studies have demonstrated that AKI is strongly associated with increased risk for development of progressive chronic kidney disease (CKD) and longer-term mortality. Much as we understand that CKD predisposes to the development of AKI, we must recognize that the relationship is bidirectional and that our patients with AKI are at risk for chronic-on-acute kidney disease.