CST3 and acute kidney injury: The Renal Angina Index, that detects minor variations in SCr along with other clinical variables, was proposed by some studies for identifying critically ill patients who are more likely to experience persistent AKI.12,13 Few studies have tried to predict the severity of renal angina and utilized plasma and/or urinary biomarkers like cystatin C, L-FABP, NGAL, IL-18, KIM-1, among others, which are time consuming and expensive to measure.7,8 In the Indian setting, some of the tools for measuring these biomarkers are not routinely available, limiting their widespread use.