Renal Recovery after Acute Kidney Injury

Until recently, patients surviving an episode of acute kidney injury (AKI) were assumed to have a good renal prognosis. This belief was predominantly based on studies that used heterogeneous AKI definitions and that considered renal recovery as dialysis independence at hospital discharge. Since standardized definitions of AKI have become available, several studies have established an association between AKI and adverse clinical outcomes. It is now well recognized that while the glomerular filtration rate generally improves after AKI, the renal recovery process is often incomplete and can result in a chronic decrease in kidney function. The loss of kidney function can vary from subclinical decreases in the glomerular filtration rate to end-stage renal disease. In this chapter, we review our current understanding of renal recovery following AKI and discuss the main studies that have established associations between AKI and the development of chronic kidney disease and end-stage renal disease.