How can we define recovery after acute kidney injury? Considerations from epidemiology and clinical trial design

The recent recognition that acute kidney injury (AKI) may lead to the development of chronic kidney disease and end-stage renal disease, with the attendant increase in mortality, has led to interest in the clinical epidemiology and the mechanistic understanding of renal recovery after an episode of AKI. At present, no uniform definition for recovery after AKI exists and various considerations should be taken into account in the development of a definition. Renal recovery after an AKI episode may affect clinical decision making around the initiation of renal replacement therapy, and has significant implication for biomarker assessment and identification of mechanistic targets to guide potential future clinical trials.