ANGPT2 and acute kidney injury: The plasma levels of angiopoietin-2 were significantly lower in patients who had no AKI within the four study days (2639 pg/ml, IQR 1422–5408 pg/ml) compared to patients who developed AKI in the subsequent 72 h after enrollment (4255 pg/ml, IQR 2656–7169 pg/ml) or patients who had AKI on enrollment day (5844 pg/ml, IQR 2693–11,447 pg/ml, Additional file 3: Fig. S3a).