In a German single-center RCT (the ELAIN trial) [223], 231 critically ill patients with stage 2 AKI and a plasma NGAL > 150 ng/ml were randomly assigned to an early group (initiation of RRT immediately after randomization) or a delayed group (initiation of RRT upon progression of AKI to stage 3 or the presence of any absolute indications); the assessment of the 90-day mortality found the latter to be significantly reduced in the early group. This evidence concerns the gene LCN2 and acute kidney injury.