Comparing AKI severity, urine KIM-1/creatinine [median (IQR): 0.28 (0.11–0.48) vs. 0.62 (0.42–1.10), p = 0.013] and urine NGAL/creatinine [3.15 (2.15–6.67) vs. 10.8 (3.35–22.36), p = 0.030] were significantly higher in Stage 2 than Stage 1; urine TFF3/creatinine [7.77 (3.3–10.9) vs. 10.4 (6.8–16.1), p = 0.182] and serum TFF3 [1.11 (1.03–1.26) vs. 1.02 (0.79–1.26), p = 0.367] did not differ. This evidence concerns the gene TFF3 and acute kidney injury.