FGF23 and acute kidney injury: Our findings regarding the predictive value of preoperative FGF23 levels regarding post-HMII/3 mortality are similar to those reported by Speer et al. [5], who found—in a prospective cohort study involving 859 patients undergoing cardiac surgery—that preoperatively measured FGF23 levels possess equivalent prognostic significance to the established EuroSCOREII in predicting postoperative complications (e.g., AKI and nonocclusive mesenteric ischemia) as well as overall outcomes.