CALCA and acute kidney injury: PCT is recently put forward as a diagnostic marker of systemic bacterial infection and sepsis [8]–[10], which are the leading causes of acute kidney injury (AKI) in critically ill patients [11]–[14], and multiple studies [15]show that PCT levels are very high in patients with AP, and it has potential value in assessment of the severity and outcome of AP, which often are accompanied by translocation of lipopolysaccharide or other bacterial products from the gut to the systemic circulation [16].