CST3 and acute kidney injury: Pooled analysis showed that Cystatin C levels in patients with AKI was 1.562 ± 0.885 mg/dL, compared to 0.811 ± 0.108 mg/dL for patients without AKI (SMD = 4.56; 95%CI: 0.27 to 8.85; p = 0.04; Figure 4).