Critical Care Nephrology

Abstract

Acute kidney injury (AKI) is a growing clinical challenge for health care providers. AKI, even when mild, has been associated with incremental risk of short- and long-term complications. The diagnosis of AKI is traditionally based on a rise in serum creatinine and/or fall in urine output. The definition has evolved from the Risk, Injury, Failure, Loss, End-stage (RIFLE) criteria in 2004 to the AKI Network (AKIN) classification in 2007. In 2012, both were merged resulting in the Kidney Disease Improving Global Outcomes (KDIGO) classification. Significant progress has been made in the detection and validation of new biomarkers for AKI to replace or complement serum creatinine. They vary in their anatomical origin, physiological function, time of release after the onset of renal injury, kinetics, and distribution. In addition to diagnosing AKI earlier, some of them may also provide information about the underlying aetiology and indicate different stages of the pathophysiological processes involved in AKI from acute injury to recovery New biomarkers for AKI can be stratified into markers primarily reflecting glomerular filtration (i.e.