CST3 and acute kidney injury: Accordingly, we conducted a prospective, exploratory observational study to investigate the value of plasma endostatin as an early biomarker of AKI by comparing it with traditional clinical assessments of renal function and with plasma neutrophil gelatinase-associated lipocalin (NGAL) and plasma cystatin C. We hypothesized that, in patients with normal renal function on ICU admission, plasma endostatin levels would be higher among those patients who subsequently develop AKI compared with those who do not.