Among children who had both serum renin and uNGAL measured (n=182), renin was comparable to uNGAL as a biomarker of AKI with an AUC of 0.72 (95%CI, 0.63-0.81) compared to 0.70 (95%CI, 0.62-0.79), respectively (p=0.72). Here, REN is linked to acute kidney injury.