Schunk SJ, Zarbock A, Meersch M, et al. - Thorugh an observational cohort study involving 733 individuals who had elective cardiac surgery at the Saarland University Medical Centre and those who were undergoing elective cardiac surgery, experts investigated the clinical utility of urinary dickkopf-3 (DKK3), a renal tubular stress marker, for preoperative recognition of individuals at risk for acute kidney injury (AKI) and subsequent kidney function loss. Urinary concentrations of DKK3 to creatinine that were greater than 471 pg/mg, were related to significantly elevated risk for AKI, independent of baseline kidney function. Urinary concentrations of DKK3:creatinine significantly enhanced AKI prognostication in comparison with clinical and other laboratory measurements. High urinary DKK3:creatinine concentrations had an independent correlation with significantly lower kidney function at hospital discharge and following a median follow-up of 820 days. In contrast with DKK3:creatinine concentrations of 471 pg/mg or less, preoperative urinary DKK3:creatinine concentrations greater than 471 pg/mg was related to a significantly greater risk for AKI, persistent renal dysfunction, and dialysis dependency following 90 days, in the RenalRIP trial. Urinary DKK3:creatinine concentrations greater than 471 pg/mg were correlated with a significantly greater risk for AKI and persistent renal dysfunction only in individuals having a sham procedure, although, not remote ischaemic preconditioning. Therefore, for postoperative AKI and for the subsequent loss of kidney function, preoperative urinary DKK3 was an independent predictor. Moreover, in individuals in whom preventive treatment strategies are efficient, urinary DKK3 might help in the recognition.