Elevation of serum phosphorus, an early biomarker of acute kidney injury after cardiac sugery?

Methods In this retrospective diagnostic validation study of 547 patients admitted in our institute between January 2012 and December 2012, we excluded patients with end stage renal disease (clearance < 15mL / min / 1.73m2) or dialyzed, solitary kidney or nephrectomy, lack of data. Serum creatinine (Cr) and Ph were measured preoperatively and postoperatively specifically (H0, H12, H24, H48, H72). The percentage of maximum elevation of Ph (%EPh = [(maximum -minimum) / minimum] * 100) was calculated. AKI was defined as an increase Cr more than 26.5 mmol / L in 48 hours according to KDIGO criteria [2]. The diagnostic performance of postoperative Ph thresholds were analysed by elaborating area under the receiver operating characteristic curves (AUC-ROC) with sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV).