Use of biomarkers to assess prognosis and guide management of patients with acute kidney injury.

Several new biomarkers of kidney damage have been characterized and are being validated in clinical studies. These damage biomarkers complement existing conventional biomarkers of kidney function (e.g. serum creatinine, serum urea, and urine output) that are currently utilized to diagnose and stage acute kidney injury (AKI). Both functional and damage biomarkers provide an opportunity to identify patients with AKI who are at risk for a less favorable prognosis in terms of worsening damage or further declines in kidney function and likelihood of need for renal replacement. We performed a systemic search and review of the available literature pre-conference. Our workgroup presented the findings in multiple rounds to the ADQI conference members and a final summary and review was refined in an iterative approach. The specific clinical situations of renal or liver transplantation, or cirrhosis/hepatorenal syndrome were not included. Overall, multiple AKI biomarkers have been well characterized for utilization for AKI prognosis. These functional and damage markers can be used to assist in decisions related to triage of patients with AKI and identifying patients with who are at risk for progression. Set cut-offs for various biomarkers and their bedside utility are forthcoming and will be in part determined by regulatory intended use guidelines, platform standardization, and inter-laboratory calibration. There remain many unresolved areas of AKI biomarker use in selected syndromes of AKI (e.g. cardiorenal syndrome, hepatorenal syndrome). As clinicians gain experience with AKI biomarkers, clinical care plans that incorporate them into routine care will shortly follow.